Fatigue Crack Growth Analysis of Mild Steel Plate Welded by Friction Stir Welding
Fatigue Crack Growth Analysis of Mild Steel Plate Welded by Friction Stir Welding
K.N. Pandey Saurabh Kumar Gupta
Professor Research Scholar
Mechanical Engineering Department Mechanical Engineering Department
Motilal Nehru National Institute of Technology Motilal Nehru National Institute of Technology Allahabad, 211004, India Allahabad, 211004, India
ABSTRACT
Parts and structures are often welded together in different ways, as it is cost and weight effective in comparison to conventional bolted and riveted joints. Steel followed by aluminum alloys, are the most frequently welded metal. Welding results in inhomogeneous and different materials near the joint which may lead to defects. These defects may be the cause of initiation and development of cracks as a result of cyclic loading. In the present work fatigue crack growth rate of a mild steel plate welded by friction stir welding (FSW) has been studied under constant amplitude load with different values of R-ratio. Hardness in the base metal was found to be low in comparison to thermo-mechanically affected and weld nugget zone. Grain size of weld zone was much smaller to base metal and it was the same to heat affected zone and base metal. A C-T specimen with notch at welded and non welded region was tested to get the behavior of Fatigue Crack Growth (FCG) at different zones. It has been found that the fatigue crack growth rate in welded material is lower as compared to base material. INTRODUCTION
Friction stir welding (FSW) is a solid-state joining process that was invented by W. Thomas and his colleagues at The Welding Institute (TWI) of the United Kingdom in 1991 [1]. Friction stir welding has a wide application in ship building, aerospace, automobile and other manufacturing industries.
In FSW a non-consumable rotating tool which consists of a pin and shoulder is inserted into the joining edges of sheets or plates those are joined. The tool serves mainly two functions, that is, heating of the work-piece and movement of material to produce the joint. Heat is generated within the work-piece by friction between the rotating tool pin and shoulder. The localized heating plasticize the material around the pin and combination of the tool rotation and translation, transport the plasticize material from the front to the back of the pin where it cools and produce a high quality weld, in the solid state. Figure 1 illustrates the FSW process [2].
In figure 1, the advancing side is on the right side, where the tool rotational direction is the same as the tool traverse direction and the retreating side is on the left side, where the tool rotational direction is opposite the tool traverse direction [3].
Proceedings of the ASME 2013 International Mechanical Engineering Congress and Exposition
IMECE2013
November 15-21, 2013, San Diego, California, USA
IMECE2013-63163
Fig.1: Friction Stir Welding Process
FSW has many advantages over conventional fusion welding such as low distortion of welded plate, no requirement of any types of gas, environmental friendly and the ability to join such materials that are difficult to join by conventional fusion techniques [4].
Friction stir welding of Al alloys is relatively well established. To date, friction stir welds have been successfully produced on many of the important commercial Al alloys including the 1xxx [5], 2xxx [6-8], 5xxx [9, 10], 6xxx [11-13], and 7xxx [14, 15] families of alloys, as well as dissimilar Al alloys [16-18]. Friction stir welds also successfully joined others similar or dissimilar materials such as copper [19], Mg alloys [20], Al alloys with steel [21], Al alloys with Mg alloys [22], Al alloy with copper [23] Cu with brass [24]etc.
Failure analysis of the welded joints indicated that fatigue is the main reason for failures of weldments and nearly 70% of fatigue cracking occurs in the welded joints. Fatigue properties of the weld metal are mainly changed when there is an abrupt change in section caused by excess weld reinforcement, undercut, slag inclusion and lack of penetration. A. Pirondi et al. [25] analyzed the fatigue crack propagation resistance of FS welded metal-matrix composites, namely 6061 Al alloy with 20 vol. % of Al2O3(W6A20A) and 7005 Al alloy with 10 vol. % of Al2O3 (W7A10A). Authors observed that the crack propagation rate is lower in W6A20A than the base material while it is higher in the case of W7A10A and fracture toughness of the FSW joint is about 25% lower than the parent material in the case of W6A20A while it is 10–20% higher in the case of W7A10A. P.M.G.P Moreira et al. [26] determined the fatigue crack growth rates for 6082-T6 Al alloy weldment in different locations of the weldment, namely the base material, stir zone (SZ) and heat affected zone (HAZ) of weldment. Lower crack propagation rate was found for the SZ in comparison with the HAZ or even the base material. P.M.G.P. Moreira et al.
[27] compared the fatigue crack growth rates in FS welded 6082-T6 and 6061-T6 Al alloys. In both FS weldments, better crack propagation resistance was observed than the base material. The 6082-T6 and 6061-T6 base materials show very similar crack propagation behaviours. On the other hand, the friction stir 6061-T6 material shows lower crack propagation rates than corresponding 6082-T6 friction stir material. HuseyinUzun et al. [28] joined the 6013-T4 Al alloy and X5CrNi18-10 stainless steel by FSW technique and observed that fatigue properties of 6013-T4/X5CrNi18-10 joints were approximately 30% lower than that of the Al 6013-T6 alloy base metal. P. Cavaliere et al. [29] found that the presence of FSW line reduced the fatigue behaviour, but in comparison to base materials it was acceptable and considered the FSW as an alternative technique to joining for dissimilar 2024/7075 Al alloys. P. Cavaliere et al. [30] found that fatigue life of 2024/ 6082 Al alloys joints quite similar of FSW 6082 Al alloy, while for lower stresses and higher number of cycles there behaviour was much closer to that of FSW 2024 Al alloy joints.
The residual stresses developed during the welding process can significantly reduce the performance of the welds with respect to fatigue properties. The crack growth behavior in friction stir welded material is a function of microstructure, residual stresses and specimen geometry. G. Bussu et al. [31] investigated the effects of weld residual stress and heat affected zone on the fatigue crack propagation of parallel and orthogonal direction to the joint line of FS Welded 2024-T351 Al alloy. Fatigue crack growth rates both faster and slower than the base material were observed, depending on the crack orientation and distance from the weld line. The crack growth results indicated that residual stresses play a key role in the crack growth.
G. Pouget et al. [32] also showed that fatigue crack propagation in friction stir welded 2050 was strongly connected with the presence of residual stresses in weldments. Compressive residual stress in weldment improved the fatigue behavior and tensile residual stress decreased the fatigue behaviour of weldments. Tran Hung Tra et al. [33] studied the roles of residual stress and microstructure on fatigue crack propagation (FCP) behaviour in FSW of AA6063-T5 for both the welded and post weld heat treated condition. In both conditions, the FCP rate in the weld zone was higher than that in the BM. The role of residual stress was not so significant, but rather the inhomogeneous microstructure played more effectively. P.S. Pao et al. [34] investigated the effect of welding speed and microstructure on the fatigue crack growth rate of FS welded Ti-5111. Fatigue crack growth rate was significantly lower, and fatigue crack growth threshold was significantly higher through the weld than the base material. As the weld speed increases, the fatigue crack growth rate was progressively higher and fatigue crack growth threshold lower through the weld. H.J.K. Lemmen et al. [35] investigated the fatigue initiation (FI) behaviour in FS welded joints of 2024-T3 Al alloy. The FI behaviour in weldment was dependent on the presence of residual stresses, which are negligible perpendicular to the weld but significant parallel to the weld. The microstructure in the FS weld has an influence on the FI behaviour, but this effect was smaller than the influence of residual stresses.
Stress ratio and size of specimens also effects the fatigue crack growth rate. K.V. Jata et al.
[36] analyzed the FSW effect on microstructure and fatigue of Al alloy 7050-T7451. At a stress ratio of R = 0.33, the fatigue crack growth (FCG) resistance of the weld-nugget region decreased, while the FCG resistance of the HAZ increased compared to FCG resistance of base material. Differences in FCG resistances significantly reduced at a stress ratio of R = 0.70. Analysis of residual stresses, fatigue-crack closure and fatigue fracture surfaces suggested that the reducing the FCG resistance in the weld-nugget region was associated with an inter-granular failure mechanism whereas in the HAZ residual stresses were more effective than the microstructure for improving the FCG resistance. Yu E. Ma et al. [37] investigated the effect of specimen size on residual stress and fatigue crack growth in FS welded 2195-T8 Al alloy. For eccentrically loaded single edge notch (ESE(T)) samples crack growth rate in the 148×40 mm size sample was 10 times smaller than that of parent material at R = 0.1 and at R = 0.6, crack growth rates in 370×100 and 185×50 further reduced by factors of 4 and 2 compared with parent material. The crack growth rate at R = 0.6 of the 148×40 mm sample was similar to parent material. These growth rate differences are associated with residual stress field changes for the different sample sizes. In CT specimens, crack growth rates were 5–10 times slower than in the parent material [37].
The effect of residual stress can be decreased by various surface treatment processes such as laser peening, shot peening etc. Omar Hatamleh [38-39] studied the effects of various surface treatment techniques on the fatigue crack growth performance of FS welded 2195 Al alloy. The results indicated reduction in fatigue crack growth rates using laser peening compared to the native welded specimens. Measurement of residual stresses indicated that laser peening introduced higher and deeper compressive stresses compared to the shot peening. The fatigue striations spacing were smaller for the laser peened specimens when compared with the shot peened and un-peened specimens. The reduction of striation spacing indicated that slower FCG rate and the deeper compressive residual stress induced by the laser peening [39].
M. Pedemonte et al. [40] investigated the effect of the welded surface finishing treatment on the fatigue behavior of AA8090 FSW butt joints and found higher fatigue resistance of finished specimens with respect to the welded joints.
Omar Hatamleh et al. [41] analyzed the effect of laser and shot peening on the fatigue crack growth performance of FS welded 7075 Al alloy at different stress ratio. Authors observed that the number of cycles to crack initiation increased for laser peened specimen (fatigue crack growth rate is low) over shot peened, and number of cycles was increased by a factor of approximately three times for R = 0.1 and a factor of approximately two times for R = 0.7.
Compared to other conventional welding processes, FSW produced high strength, defect free and high fatigue resistance welded joints. S. Malarvizhi et al. [42] studied the fatigue crack growth resistance of gas tungsten arc (GTA), electron beam (EB) and FS welded joints of AA2219 Al alloy. Authors found that the FSW weldment was exhibited higher fatigue crack growth resistance compared to EBW and GTAW weldment. This was mainly due to the uniform distribution of fine precipitates of very fine grains in the weld region. G. Padmanaban et al. [43] compared the fatigue crack growth behaviour of pulsed current gas tungsten arc welding (PCGTAW), FSW and laser beam welding (LBW) of AZ31B Mg alloy. The joints fabricated by an LBW process offered greater resistance against fatigue crack growth compared to PCGTAW and FSW joints. P.M.G.P. Moreira et al. [44] compared the fatigue behaviour of FSW and MIG weldments of two Al alloys. The FS welded 6061-T6 weldment presented lower fatigue lives than the FS 6082-T6 weldment when tested at stresses lower than 130 MPa. Fatigue lives of MIG weldments for both Al alloys were lower than the FS weldment. The MIG welded 6061-T6 joint presented higher fatigue lives than the MIG 6082-T6 joint [44].
From the literature review, it was observed that there is still need of study of fatigue behavior of FS Welded mild steel plate. The major objectives of this work was to demonstrate the feasibility of FSW for joining of mild steel by characterizing the process, microstructures, and mechanical properties of friction stir welds on mild steel.
Material%C %Mn%P %S %Si Mild
steel
0.180.82 0.0110.006<0.001 Tab. 1: Chemical composition of base material
EXPERIMENTAL PROCEDURE
In this study, 3 mm thick mild steel plate welded by FSW with the welding direction parallel to the rolling direction of the plates was used to characterize the weldment. The chemical composition of mild steel was given in Tab 1. Welds were made in the butt-joint configuration on
samples typically 200 mm in length and 5width. Vertical Milling Machine (HMT,with special attachment was used to fabric joints using optimized FSW paramet shoulder diameter of the tool was 15 mm pin length was 2.7mm. Tool material was carbide with cylindrical threaded pin . Fri welds were produced at 80 mm/min weld with tool rotating at 700 revolutions pe (rpm). A xial force was 7 KN during we Welded joint of mild steel plate is shown in
Fig. 2: Friction stir welded Mild steel pla
Tensile tests were performed to
find tensile properties of the welded and base such as yield strength, ultimate tensile stre percentage of elongation. The tensile test s were prepared by wire-cut electro machine as per ASTM E08-04 standards tests were carried out using a 100 k testing machine. A Vickers micro hardn (Shimadzu) was employed for me asu hardness across the joint with a load of 1 N dwell time. Microstructural analysis was c to study microstructure of friction stir weld light optical microscope. The fatigue te conducted at room temperature in laborato a servo-hydraulic testing machine (MTS) o capacity under constant amplitude conditions. Fatigue crack growth r investigated for both base material (BM
welded material. The test was carried out a and 50 mm in HMT, 7 H.P.) fabricate FSW rameters. The 5 mm, and the al was tungsten Friction stir welding speed ns per minute g welding. FS own in fig . 2.
eel plate o find out the d base material le strength and test specimens ctro discharge ndards. Tensile N universal hardness tester asuring the of 1 N and 30 s was carried out r welds using a gue tests were boratory air on MTS) of 100 kN tude loading th rate was ) and FS d out according
to ASTM E647 standard co specimen . Dimensions th shown in fig. 3.
Fig. 3: Di mension of Compact
specimen and FS Welded spec
Constant amplitude frequency of 20 Hz and stress
0.2 was applied in atmos temperature to get fatigue specimen with clevis and pin stress intensity factor range equation (1). Finally, the expe crack growth rate da/dN were of range of stress intensit logarithmic scale. The experi correlated using the Paris law.886.0()
1()2(2
/32/1αα+?+?=?BW P K W a /=α, a = crack length specimen in mm, B = Thick mm, ?P = P max - P min
Fig. 4: CT specimen wit
rd compact tension (CT) of the CT specimens are
mpact Tension (CT) d specimen for fatigue test itude cyclic load at a stress ratio (R) of 0.1 and atmospheric air at room igue crack growth . C(T) d pin is shown in fig. 4. The nge ?K is calculated from experimental results of the were plotted as a function tensity factor, ?K in a experimental data was also s law.
)6.572.1432.1364.44
32αααα?+? (1) ength in mm ,W = Width of Thickness of specimen in
en with clevis and pin
RESULT AND DISCUSSIONS
Microstructural examination of the base material and welded joint, by optical microscope is showed in fig 5.Figure 5 (a) shows the microstructure of the FS welded material and Fig. 5(b) shows the microstructure of the base material. As observed, the microstructure of base material contains two sizes of grains. The recrystallized grains are approximately 20 μm in size while the non-recrystallized grains can be larger than 100 μm. Microstructure analysis of the welded material shows dynamic recrystallized grains much smaller size at the weld nugget zone as compared to the base metal microstructure. In the HAZ, the grain size is similar to the base metal.
Fig. 5: (a) Microstructure of the FS weld material
(b) Microstructure of the base material
Material Yield
strength
(MPa) Ultimate
tensile
strength
(MPa)
% of
Elongation
Base
Material
286 389 34 FS welded
Material
310 405 26 Tab. 2: Tensile properties for base material and Friction stir welded material
The results of the tensile tests
for
the base
material and after the FSW process are reported in Tab. 2. From the data of tension test, Tab. 2, it can be
seen that
the FSW process led to a increase of the yield strength and ultimate tensile strength, and also to a reduction of the elongation to failure.
A profile of the micro-hardness data as a function of distance from the weld centerline is presented in fig.6. The micro-hardness value of base material was approximately 135 HV. The micro-hardness value of the stir zone varied with position ranging from 155 to 175 HV, depending on the grain size.
Fig.6: Micro-hardness profile of friction stir
welded Mild steel
Hardness decreased with increasing distance from the stir zone from approximately 150 to 160 HV in the HAZ and between 135 to 140 HV in the base metal.
Fig. 7: Fatigue propagation data for BM and welded specimen at R = 0.1
Fig. 8: Fatigue propagation data for BM and welded specimen at (a) R = 0.1
Fig. 7 and 8 summarizes the fatigue crack growth rate results obtained for the BM and friction stir welded material at R=0.1 and R=0.2. As shown in fig. 7 and 8, the fatigue crack growth rate for FS welded specimen is lower compared to fatigue crack growth rate for base material at R = 0.1 but on the other hand fatigue crack growth rate at R = 0.2 is higher for FS welded specimen. The fig. 7 and 8 also include the Paris’s law correlation which is achieved for very high correlation coefficients. Fatigue life of welded specimen is higher as compare to base material specimen. Fatigue life of the welded plate is 61400 cycles and 67900 at stress ratio 0.1, 0.2 respectively. Life of the base material specimen is 51500 cycles and 58500 cycles at stress ratio 0.1 and 0.2 respectively. Fig. 9 shows the fractured specimen after fatigue test.
Fig. 9. Fractured C(T) speciumen after fatigue test CONCLUSION
From this investigation following important conclusions were derived.
1.Grain size at the weld nugget zone is smaller
than the base material but, on the other hand
grain size at HAZ is similar to the base
material for mild steel.
2.The average value of micro-hardness at SZ
and TMAZ is higher as compared to other
HAZ and base material.
3.Results of this study have demonstrated the
feasibility of FSW of mild steel without loss
of tensile properties. Based on these results,
FSW of HSLA steels and stainless steels
may be feasible.
4.The friction stir welded material revealed
higher yield and ultimate strength than the
base material as well as lower elongation.
5.No significant change in crack growth rate
was observed between base metal and
welded material for R = 0.1 whereas for R =
0.2 fatigue crack growth was more for base
material than welded material. This
difference was increasing with increase in
?K.
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Authors
1.Dr.K.N.Pandey
Professor
Mechanical Engineering Department
Motilal Nehru National Institute of
Technology
Allahabad – 211 004
knpandey@mnnit.ac.in
2.Mr.Saurabh Kumar Gupta
Mechanical Engineering Department
Motilal Nehru National Institute of
Technology
Allahabad – 211 004
saurabhguptanit@https://www.wendangku.net/doc/d015954483.html,
超详细Abaqus安装教程
超详细A b a q u s安装教 程 Pleasure Group Office【T985AB-B866SYT-B182C-BS682T-STT18】
Abaqus2017 安装教程 将安装镜像加载至虚拟光驱 以管理员身份运行J:\1下的,保持默认点击下一步。 首先安装的是拓展产品文档，点击“下一步”，选择安装目标，并点击“下一步” 选择文档需要包含的部件，并点击“下一步” 提示程序安装信息足够，点击“安装” 提示SIMULIA 2017文档安装成功，点击“关闭”。 接着会自动弹出Abaqus Simulation Services,修改安装目标地址，并点击“下一步” 选择您需要的部件，并点击“下一步” 检测安装信息足够，点击“安装”， 提示安装成功够点击“关闭” 接来下会自动安装Abaqus Simulation Services CAA API，点击“下一步”， 选择您需要的安装的部件，点击下一步 安装完成后“关闭” 接下来是自动安装 Abaqus CAE 找到安装包里的_SolidSQUAD_文件夹，将里面的License文件复制到Abaqus安装目录里的SIMULIA文件夹里。然后打开License文件夹，改.lic许可证文件的计算机名，同时再新建一个.log日志文件。 粘贴到D:\SIMULIA 下 在License下新建一个文本文档，重命名为 用记事本打开 使用计算机名替换this_host 保存后退出。 以管理员方式打开，点击Config Services，按如下配置 点击Save Service。切换到Start/Stop/Reread选项卡，点击Stop Server，再点击Start Server。下面提示Server Start Successful则配置成功。关闭窗口。 回到Abaqus CAE的安装界面。 在License Server 1 中输入27011@DESKTOP-Q8CNNLR 注：DESKTOP- Q8CNNLR 是计算机的用户名。点击下一步。 点击下一步 修改目录，点击下一步 设置工作空间路径，建议选择较大的硬盘分区。点击“下一步” 信息确认无误开始安装。 点击Continue 提示Abaqus CAE安装完成，点击关闭。 下面是Tosca 2017的安装。根据需求选择安装。 根据需求选择接口 若安装按ANSA可选择路径，没有则直接下一步。 若没有安装Fluent ,取消勾选FLUENT 剩下步骤类似上面。最后点击安装。 最后是 Isight 2017的安装。步骤后之前相同，一直点下一步记忆可以了
LMS TecWare疲劳载荷处理软件
疲劳载荷处理软件（LMS T ecWare）技术指标 ?系统要求 -操作系统：WindowsNT/2000， HP UX， SGI， Sun 工作站 ?任务管理和载荷时间历程管理（T ecW are Kernel 模块） -同时读入不同格式的多个文件中的任意多个时间历程，单个或多个同时显示、编辑 -时域信号编辑功能：同时对多个通道进行积分、微分、时间段剪切/粘贴、偏移/零点漂移初步矫正、数据平滑、函数生成时间历程信号、自动选择时间段… -可轻松地将时域信号在几种格式之间相互转换 -袖珍计算器和逻辑操作功能，根据数学函数生成时间历程 -桌面管理器用来管理所有数据对象并监控分析任务 -结果自动添加到当前桌面管理器中 -完全可自定义的用户界面（如菜单、按扭等） ?疲劳计数（T ecW are FatiCount 模块） -Rainflow（雨流），Range pair（程对）、level crossing（穿级）, symmetrical level crossing（对称穿级）, Peak Count（峰值计数）III … -一次批作业设置可以处理多个时间历程和通道 -交互式设置处理参数 -预定义的通用参数（滤波带宽、分级数、结果储存方案等） ?基于雨流矩阵的基本编辑和处理、重构为时间历程（T ecW are RainEdit 模块） -编辑雨流矩阵和雨流计数留数：改变分级大小和个数，对行/列/点/对角线进行计数值的修改/删除 -基于雨流矩阵的时间历程重构，进行加速模拟试验 ?基本的疲劳寿命估计(Falancs Strain & Stress 模块) -根据应变时间历程和材料特性计算该点的疲劳寿命，可以是应变片测得的时间历程 -根据载荷时间历程、应力集中系数和材料特性计算该点的疲劳寿命 -应力法和应变法多种损伤准则、均值校正 -可更改材料特性并存为新材料 ?基于雨流矩阵的载荷组合和外推（T ecW are RainExtra模块） -雨流矩阵的组合、叠加、差别比较等 -由短的时间历程生成雨流，外推到更长的使用工况 -扩展为更苛刻的载荷数据（更粗暴的驾驶员、更恶劣的试验路段等） ?耐久性试验信号处理(TecW are durability signal processing 模块) -提供处理时域信号常用的谱分析和附带交互式滤波器设计工具的频率滤波功能 -快速富氏变换（FFT）和逆变换，功率谱密度函数、频率响应函数、相干函数 -交互式滤波器设计工具：低通、高通、带通和组合式 ?高级耐久性试验信号处理(TecW are Advanced durability signal processing 模块) -检测信号异常、显示时域信号趋势。突出显示不正确的数据段，自动进行信号净化。 -自适应尖峰检测 -消除信号漂移 -逐帧信号分析 ?用多轴雨流技术进行多轴载荷分析（T ecW are MultiRain 和MultiRain Extension 模块） -把雨流矩阵扩展到包含相位影响的多轴向载荷分析 -叠加、外推为更长的测量数据，并重构为时间历程。基于雨流的所有著名的单轴向方法都扩展到多轴向。 ?多轴载荷的雨流投影滤波器(T ecW are RP filter 模块) -设定幅值大小，多通道统一滤波，显著缩短时间历程的长度，保持多轴载荷的相位特征 -保留频率特性，或者把能量损失限制在用户定义的频段内 -时间窗技术，用于保留窗内的频率特性 -试验预处理算法在需要时可以降低信号的斜率或频率
疲劳分析流程 fatigue
摘要：疲劳破坏是结构的主要失效形式，疲劳失效研究在结构安全分析中扮演着举足轻重的角色。因此结构的疲劳强度和疲劳寿命是其强度和可靠性研究的主要内容之一。机车车辆结构的疲劳设计必须服从一定的疲劳机理,并在系统结构的可靠性安全设计中考虑复合的疲劳设计技术的应用。国内的机车车辆主要结构部件的疲劳寿命评估和分析采用复合的疲劳设计技术，国外从疲劳寿命的理论计算和疲劳试验两个方面在疲劳研究和应用领域有很多新发展的理论方法和技术手段。不论国内国外，一批人几十年如一日致力于疲劳的研究，对疲劳问题研究贡献颇多。 关键词：疲劳 UIC标准疲劳载荷 IIW标准 S-N曲线机车车辆 一、国内外轨道车辆的疲劳研究现状 6月30日15时，备受关注的京沪高铁正式开通运营。作为新中国成立以来一次建设里程最长、投资最大、标准最高的高速铁路，京沪高铁贯通“三市四省”，串起京沪“经济走廊”。京沪高铁的开通，不仅乘客可以享受到便捷与实惠，沿线城市也需面对高铁带来的机遇和挑战。在享受这些待遇的同时，专家指出，各省市要想从中分得一杯羹，配套设施建设以及机车车辆的安全性绝对不容忽略。根据机车车辆的现代设计方法，对结构在要求做到尽可能轻量化的同时，也要求具备高度可靠性和足够的安全性。这两者之间常常出现矛盾，因此，如何准确研究其关键结构部件在运行中的使用寿命以及如何进行结构的抗疲劳设计是结构强度寿命预测领域研究中的前沿课题。 在随机动载作用下的结构疲劳设计更是成为当前机车车辆结构疲劳设计的研究重点，而如何预测关键结构和部件的疲劳寿命又是未来机车车辆结构疲劳设计的重要发展方向之一。机车车辆承受的外部载荷大部分是随时间而变化的循环随机载荷。在这种随机动载荷的作用下，机车车辆的许多构件都产生动态应力，引起疲劳损伤，而损伤累积后的结构破坏的形式经常是疲劳裂纹的萌生和最终结构的断裂破坏。随着国内铁路运行速度的不断提高，一些关键结构部件，如转向架的构架、牵引拉杆等都出现了一些断裂事故。因此，机车车辆的结构疲劳设计已经逐渐成为机车车辆新产品开发前期的必要过程之一，而通过有效的计算方法预测结构的疲劳寿命是结构设计的重要目标。 1.1国外 早在十九世纪后期德国工程师Wohler系统论述了疲劳寿命和循环应力的关系并提出了S-N 曲线和疲劳极限的概念以来，国内外疲劳领域的研究已经产生了大量新的研究方法和研究成果。 结构疲劳设计中主要有两方面的问题：一是用一定材料制成的构件的疲劳寿命曲线；二是结构件的工作应力谱，也就是载荷谱。载荷谱包括外部的载荷及动态特性对结构的影响。根据疲劳寿命曲线和工作应力谱的关系，有3种设计概念：静态设计(仅考虑静强度)；工作应力须低于疲劳寿命曲线的疲劳耐久限设计；根据工作强度设计，即运用实际使用条件下的载荷谱。实际载荷因为受到车辆等诸多因素的影响而有相当大的离散性，它严重地影响了载荷谱的最大应力幅值、分布函数及全部循环数。为了对疲劳寿命进行准确的评价，必须知道设计谱的存在概率，并且考虑实际载荷离散性，才可以确定结构可靠的疲劳寿命。 20世纪60年代，世界上第一条高速铁路建成，自那时起，一些国外高速铁路发达国家已经深入研究机车车辆结构轻量化带来的关键结构部件的疲劳强度和疲劳寿命预测问题。其中，包括日本对车轴和焊接构架疲劳问题的研究；法国和德国采用试验台仿真和实际线路相结合的技术开发出试验用的机车车辆疲劳分析方法；英国和美国对转向架累计损伤疲劳方面的研究等等。在这些研究中提出了大量有效的疲劳寿命的预测研究方法。 1.2、国内 1.2.1国内疲劳研究现状与方法 国内铁路相关的科研院所对结构的疲劳寿命也展开了大量的研究和分析，并且得到了很多研
workbench与其他软件联合疲劳寿命分析
联合 ANSYS WORKBENCH和DESIGNLIFE进行疲劳分析 分类： CAE 疲劳分析 ansys 疲劳失效是机械零部件失效的主要形式。如何对这些结构进行有效的疲劳分析，引起了很多产品设计工程师的关注。对于一般零部件的疲劳分析，并没有理论公式可以解决，几乎都是依据有限元技术以及疲劳分析技术。因此联合有限元分析软件和疲劳分析软件，对这些零部件进行疲劳分析，是解决这类问题的有效途径。 ANSYS WORKBENH是世界上著名的以多物理场分析为特色的有限元分析软件，而DESIGNLIFE是NCODE公司的功能强大的疲劳分析软件。本文以材料力学中中一根变截面轴的弯扭组合的疲劳分析为例，说明如何联合这两款软件对之进行疲劳分析。 问题描述如下： 一根变截面轴，左边轴段（蓝色部分）固定，而在最右边轴段上（红色部分）施加一个1N 的集中力（它导致弯曲变形）和一个1000Nmm的集中力偶（它导致扭转变形）， 对于这两种载荷的时间历程，使用力传感器进行测定94秒，得到如下图所示的时间历程曲线。 上图中的红色曲线图反应了集中力随时间的变化规律，横坐标是时间，单位是秒，这里测试了94秒。而纵坐标是载荷的大小。从图中可以看出，最大的载荷是18KN左右，而且也可
以看到，载荷的变化很不规则，并非理想的循环方式。而蓝色曲线反应的是集中力偶随时间变化的规律，其幅值在-2717到2834之间改变。 该轴的材料已经给定，是碳钢SAE1045_390_QT. 现在要求对该轴进行疲劳分析。 使用WORKBENCH和DESIGNLIFE对之进行疲劳分析，分为两步。第一步是在WORKBENCH中建立有限元模型，并分别施加集中力和集中力偶，通过计算，得到两种情况的米塞斯应力，这相当于两种工况，这样可以得到ANSYS WORKBENCH的结构分析结果文件*.rst.第二步在DESIGNLIFE中进行，首先根据疲劳分析的五框图，构造疲劳分析流程，然后分别设定各个框图的属性，即有限元结果文件，载荷文件，材料文件，疲劳分析选项，然后启动分析，通过后处理以查看轴上各点的疲劳寿命。 1. WORKBENCH中建立有限元模型并进行分析。 （1）使用designmodeler创建几何模型。 （2）设置材料属性。 （3）划分网格。 （4）设置分析选项。 这里设置两个载荷步，其目的只是分开弯曲和扭转这两种工况。
ABAQUS 2017 2018汉化教程
ABAQUS 2017 2018第一次安装后软件不能启动解决办法！ 1.打开安装盘对应的以下路径：E:\Program Files\Dassault Systemes\SimulationServices\V6R2017x\win_b64\SMA\site（软件安装在什么盘下，路径中的E更改为对应的盘符）。 2.在Site文件夹下找到custom_v6.env文件，鼠标右键点击，打开方式选择写字板（修 改custom_v6.env文件前建议先复制一份备份）。 3.将打开的custom_v6.env文件中带色的部分删除并保存。（若修改后不能保存，可 将custom_v6.env文件复制到桌面进行修改保存，然后复制并覆盖E:\Program 下的源文件） 4.双击ABAQUS 2017图标，软件已正常运行。
ABAQUS 2017 2018汉化教程！ 1.打开安装盘对应的以下路径：E:\SIMULIA\CAE\2017\win_b64\SMA\Configuration（软 件安装在什么盘下，路径中的E更改为对应的盘符）。 2.在Configuration文件夹下找到locale.txt文件，将locale.txt文件复制到桌面，鼠标右 键点击，打开方式选择写字板（修改locale.txt文件前建议先复制一份备份）。 3.在“Chinese_People's Republic of China.936 = zh_CN Chinese (Simplified)_People's Republic of China.936 = zh_CN”下方插入一行Chinese (Simplified)_China.936 = zh_CN 如下图：
abaqus与fatigue结合疲劳分析
a b a q u s与f a t i g u e结 合疲劳分析 公司标准化编码 [QQX96QT-XQQB89Q8-NQQJ6Q8-MQM9N]
Fatigue 分析实例 为如图1所示的中心孔板，材料为LY12-CZ ，板宽50mm,孔直径为8mm ，板厚1mm 。LY12-CZ 铝板弹性模量GPa E 68=，强度极限MPa b 482=σ。在板的两边施加1MPa 的均布拉应力。 图1 中心孔板结构示意图 1、应力计算结果与分析 对上述模型进行有限元计算，结果应力云图如图2所示。
图2 应力云图 2、*.Fil文件说明 *.fil文件是ABAQUS的一种二进制输出文件，供其他软件（如Patran）后处理使用，如生成X-Y曲线，制作二维表格等，可以输出的项目包括：单元、节点、接触面、能量、模态、梁截面等的输出信息，输出的方法是在INP文件中增加输出指令， 生成*.fil文件的步骤如下 对ABAQUS/Standard，可以直接输出.fil文件，步骤如下： 在inp文件中，step步骤之后， end step步骤之前，加上以下内容：
*NODE FILE RF,U,V **输出节点的作用力(RF)，位移(U,V)到*.fil中 *EL FILE S,E **输出单元应力(S)，应变(E)到*.fil中 在abaqus的job界面重新运行inp文件，即可得到对应的fil文件3、疲劳寿命估算 疲劳寿命估算需用到软件中的模块。如图3所示，位于的Tools菜单下，点击Main Interface即可进入模块主界面。 图3 在中进入界面
疲劳分析计算的流程
疲劳分析，从零开始 1 测量应变、应力谱图 （1）衡量应力集中的区域，布置应变片 可以通过模拟（有限元）或试验（原型上涂上一层油漆，待油漆干后施加载荷，油漆剥落的地方应力集中），确定应力集中的区域，然后按左下图在应力集中区域布置三个应变片： 因为材料是各向同性，所以x,y方向并不一定是水平和竖直方向，但两者一定要垂直，中间一个一定要和x,y方向成45°角。 （2）根据测的应变和材料性能，计算应力 测得的三个应变，分别记为εx, εy, εxy。两个主应力（假设只有弹性变形）： 其中，E为材料的弹性模量，μ为泊松比。根据这两个主应力，可以计算出有些方法可能需要的等效应力（主要目的是将多分量的应力状态转化为一个数值，以方便应用材料的疲劳数据），如米塞斯等效应力：
()()222122121σσσσσ++-=m 或最大剪应力： ()2121 σσστ-= 实际测量的是应变-时间谱图，应力（或等效应力）-时间谱图可由上述公式计算。 （３）分解谱图 就是对上面测得的应力（应变）－时间谱图进行分解统计，计算出不同应力（包括幅度和平均值）循环下的次数，以便计算累积的损伤。最常用的是雨流法（rainflow counting method ）。 2 获取材料数据 如果载荷频率不高，可以做一组简单的疲劳测试（正弦应力，拉压或弯曲均可，有国家标准）： 得到一条应力-寿命（即循环次数）曲线，即所谓的S-N 曲线：
1：如果载荷频率较高或温度变化较大，还要测量不同平均应力和不同温度下的S-N 载荷，以便进行插值计算，因为此时平均应力对寿命有影响。也可以根据不同的经验公式（如Ｇｏｏｄｍａｎ准则，Ｇｅｒｂｅｒ准则等），以及其他材料性能（如拉伸强度，破坏强度等），由普通的Ｓ－Ｎ曲线（即平均应力为０）来计算平均应力不为零时对应的疲劳寿命。 2：如果材料数据极为有限，或者公司很穷很懒不愿做疲劳试验，也可以由材料的强度估算疲劳性能。 3：:如果出现塑性应变，累计损伤一般基于应变－寿命曲线（即Ｅ－Ｎ曲线），所以需要施加应变载荷。 3 损伤计算 到目前为止，疲劳分析基本上是基于经验公式，还没有完全统一的理论。损伤 累积的计算方法有很多种，最常用的是线性累计损伤（即Ｍiner 准则）， 但其结果不保守，计算得到的寿命偏高。 ∑∑≥=0.1,f i i i N n D 准确度比较高的累计准则是双线性准则，并且计算比“破坏曲线法”要容易，所以，是一个很好的折衷选择。
结构疲劳分析技术新进展
媒体文章 结构疲劳分析技术新进展 安世亚太 雷先华 众所周知，疲劳累积损伤是导致航空产品结构失效的主要原因之一，而结构失效往往给航空器带来灾难性后果，因而在现代航空产品设计中通常要求进行较为准确的结构疲劳寿命预测。由于疲劳的形式和影响结构疲劳的因素都非常繁多，因而并没有一套放之四海而皆准的疲劳寿命预测算法，多数算法都只能在某些特定情况下才能获得满足工程精度要求的预测结果。现代疲劳分析软件通常需要在通用疲劳算法的丰富性和先进性（核心）、有限元应力应变计算的准确性和精确性（基础）、以及针对特殊疲劳问题进行处理的方法多样性和完整性（全面）等方面进行持续不断的改进方能较好地满足工程设计的要求。下面我们以安世亚太高级疲劳分析软件Fe-safe为例，简要阐述其在这些方面的新进展。 1．基于临界平面法的精确多轴疲劳算法 航空器上的零部件通常都是在多轴疲劳载荷作用下工作，此时，材料的循环应力应变关系由于受到加载路径的影响而变得相当复杂。目前，多轴疲劳破坏的准则主要有三大类：应力准则、应变准则和能量准则。众多分析及试验对比证明，组合最大剪应变和法向应变的Brown-Miller准则和Wang-Brown准则对于韧性材料具有最好的计算精度，而主应变准则则适合于脆性材料。 对于航空结构中常见的、而且是最复杂的多轴非比例加载情况，由于载荷间的相位关系在不断变化，结构中每个位置点处的主应力/应变、最大剪应力/应变等参数的方向（所在平面）都是随加载历程而不断变化的，也就是说损伤累积在每个位置处都有方向性。对于很多软件所采用的Wang-Brown准则，它无法直接考虑这种方向变化性，只是利用了一个附加的材料参数来考虑法向应变对裂纹萌生的影响。 Fe-safe独特地提供了“临界平面”算法来配合Brown-Miller准则、主应变准则等，以获得最好的计算精度。临界平面法的核心思想是：将每个位置处的应变分解到按某种规律变化的一系列平面上，计算每个平面上的损伤，以这些平面中的最小寿命作为该位置的寿命。 2．独特的焊接结构疲劳算法 焊接连接是航空器上非常常见的结构连接方式，在航空结构设计中具有非常重要的地位，但焊接部位同时也是最容易产生疲劳裂纹问题的位置。现有疲劳分析软件几乎无一例外都是按照“焊接分类”（如英国BS7608标准）的方法来进行焊接结构疲劳分析的，该方法在大量工程实例的基础上根据预期的疲劳裂纹位置而将焊接结构分为数个类型（B、C、D、E、F、F2、G、W等），每个类型对应一条相互平行的S-N曲线用于疲劳评估。因此，在焊接结构疲劳分析中存在两个主要问题极大地影响了其工程应用：一是焊接分类的标准难以把握（事实上焊接类型是无穷多的）；二是由于焊接位置通常都是应力集中位置，难以精确计算应力分布。
Msc.Fatigue疲劳分析实例指导教程
第三章疲劳载荷谱的统计处理 3.1 疲劳载荷谱的统计处理理论基础 3.1.1 数字化滤波 频率分析的典型参量是功率谱密度（PSD），如像确定频率为4Hz对应的幅值的均方根值，只需要求取功率谱密度下对应的3.5-4Hz之间的面积。 3.1.2 雨流计数法 循环计数法：将不规则的随机载荷-时间历程，转化为一系列循环的方法。 3.2 数据的导入与显示 （1）新建：File>New （2）导入：Tools>Fatigue Utilities>File Conversion Utilities>Covert ASCII.dac to Binary...>Single Channel（设置，注意Header Lines to skip要跳过的行数）>exit （3）查看：Tools>Fatigue Utilities>Graphic Display>Quick Look Display 1）放大：View>Window X，输入X的最值 2）读取：①左击任何位置，状态栏显示②数据轨迹：Display>Track 3）显示数据点：Display>Join Points；显示实线图：Display>Join 4）网格和可选坐标轴：Axes>Axes Type/Grid 5）显示某段时间信号的统计信息：Display>Wstats，放大 3.3 数字滤波去除电压干扰信号 （1）载荷时间历程的PSD分析 1）File>New 2）Tools>Fatigue Utilities>Advanced Load Utilities>Auto Spectral density （2）信号的滤波 1）Tools>Fatigue Utilites>Advanced Load Utilities>Fast Fourier Filtering 2）比较滤波前后结果：Tools>Fatigue Utilities>Graphic Display>Multi-file Display （3）滤波稳定性检查：比较前后PSD，多文件叠加显示 第四章应力疲劳分析 4.2 载荷谱块的创建与疲劳寿命计算 （1）创建载荷谱块：Tools>Fatigur Utility>Load Management>Add an Entry>Block program （2）疲劳分析：Tools>Fatigue Utilities>Advanced fatigue utilities>选方法 4.3 零部件疲劳分析 （1）导入有限元模型及应力结果：工具栏Import>Action、Object、Method，查看Results （2）疲劳分析 1）设置疲劳分析方法：工具栏Analysis，设置 2）设置疲劳载荷 ①创建载荷时间历程文件Loading info>Time History Manager ②将有限元分析工况与时间载荷关联：Loading Info>Load case空白>Get/Filte result...
有限元软件进行疲劳分析的若干问题
首先要明确我们大体上遇到的疲劳问题均为高周疲劳问题（当然不排除个别如压力容器和燃气轮机的零件疲劳问题），应力水平较低，破坏循环次数一般大于十的四次方或五次方。疲劳设计和寿命预测方法一般有无限长寿命设计法和有限寿命设计法。无限寿命设计法使用的是S-N曲线的右段水平部分（疲劳极限），而有限寿命设计法使用的是S-N曲线的左段斜线部分。有限寿命设计的设计应力一般高于疲劳极限，这时就不能只考虑最高应力，而要按照一定的累积损伤理论估算总的疲劳损伤。 大多数零件所受循环载荷的幅值都是变化的，也就是说，大多数零件都是在变幅载荷下工作。变幅载荷下的疲劳破坏，是不同频率和幅值的载荷所造成的损伤逐渐积累的结果。因此，疲劳累计损伤是有限寿命设计的核心问题。 一般常用三种累积损伤理论，其各自适用范围如下： 线性疲劳累积损伤理论适合于高周疲劳寿命计算，可较好地预测疲劳寿命均值。线性累计损伤理论指的是损伤积累与循环次数成线性关系，包括Miner法则和相对Miner法则；Miner 理论的表达式为（D为损伤） 修正的线性疲劳累积损伤理论适合于低周疲劳寿命计算； 而非线性疲劳累积损伤理论对二级加载情况的疲劳寿命估算比较有效。非线性累计损伤理论包括损伤曲线法和Corten-Dolan理论。 要注意的是，只有当应力高于疲劳极限时，每一循环使结构产生一定量的损伤，这种损伤是累积的；当应力低于疲劳极限时，由于此时N将无穷大，因此，它的循环便不必考虑。 国内外常用的疲劳设计方法-安全寿命法的具体步骤为： 1. 得到用于疲劳计算的载荷谱； 2. 计算构件各位置的应力历程； 3. 利用计数法（如雨流法）将应力历程整理为不同应力幅及其相应的循环次数； 4. 由S-N曲线得到应力幅对应的使用极限； 5. 利用累积损伤理论（如Miner准则）计算总损伤； 6. 计算安全寿命Ts=TL/D MSC.Fatigue软件与此方法结合的很好，然而，有限元法解决实际工程中的疲劳问题还有一些问题： 1. 目前疲劳理论对于材料微裂纹的形成和扩展过程中的某些效应无法全面彻底地分析其机理，因此在此基础上发展而来的各种方法在某些情况下可能导致结果误差很大； 2. 各种疲劳分析有限元法对应力类型及作用方式十分敏感，而实际工程中这些因素往往无法精确得到，造成结果分散性相当大； 3. 很难预先判断易发生疲劳破坏的危险区域，而想要对其中所有可能发生初始裂纹的节点进行细化建模分析目前显然不太现实； 4. 不确定因素如载荷时间历程的复杂性、模型试验结果的分散性、残余应力及腐蚀影响等，可能导致结果与实际情况存在量级上的偏差。 对于常用的疲劳分析软件Fatigue，其自带三种分析方法适用范围如下： 1. S-N曲线总寿命分析法： 疲劳寿命相当长的结构，且很少发生塑性变形； 裂纹初始化及裂纹扩展模型不适用的结构如复合材料、焊接材料、塑料以及一些非钢结构；已有针对结构的大量现成S-N数据的情形； 焊接热点区域疲劳分析以及随机振动引发的疲劳问题。 2. 适用裂纹初始化分析法的情形： 基本没有缺陷的金属构件；
Abaqus安装教程及汉化中英转换图文教程
ABAQUS安装及汉化过程 安装环境：win764位旗舰版。Abaqus-6.13.1-Win64-SSQ安装，在这之前保证自己的电脑名为英文。本文介绍安装步骤及汉化过程。排版技术有限，见谅。 一，安装步骤。 1.点击setup.exe进入安装程序。 2.点击next。 3.点击continue。
4.点击next。 5.不用勾选，直接点击next。 6.现在会自动生成主机名称，记住你的主机名，待会要用。（如果你的电脑是中文名，则生成的主机名会乱码，那么安装则会失败）。
. 7.选择第二个选项，点击next。 8.选择安装位置。同样确保为英文名称。 9.注意，现在先不要点击next。我们来破解软件。
10.打开ABAQUS_6.13.1_Win64_SSQ\_Crack_目录下ABAQUS.lic，用记事本打开。修改此处计算机名为自己的计算机名，我的是PC。 11.把这修改好的文件.lic和.Log复制到安装目录D:\ABAQUS\License下。
12.打开此文件夹下imtool.exe,进行设置。 点击config services，选择安装目录下的lmgrd.exe abaqus.lic abaqus.log文件如图所示，点击save service保存设置。
点击start server，确保下方提示successful。现在可以关闭lomtools了。 13.新建系统变量，右键点击计算机，点击属性，进入高级系统设置。高级栏下点击环境变量。 在系统变量中添加如下变量。 14.继续安装，点击next。
疲劳分析软件 ANSYS FE_SAFE 简介(转)
问题1：ANSYS后处理疲劳功能与ANSYS/Fe-safe疲劳功能的关系是什么？ 回答1：ANSYS后处理疲劳功能是依据线性累积损伤理论，利用S-N曲线、应力时间历程以及雨流计数技术直接计算疲劳寿命使用系数，属于简单的名义应力疲劳寿命评估，对疲劳的影响因素的考虑有限，适用于粗略估算。ANSYS/Fe-safe则是专用的高级疲劳分析模块，采用先进的单/双轴疲劳计算方法，允许计算弹性或弹塑性载荷历程，综合多种影响因素（如平均应力、应力集中、缺口敏感性、（焊接成型等）初始应力、表面光洁度、表面加工性质等），按照累积损伤理论和雨流计数，根据各种应力或应变进行疲劳寿命和耐久性分析设计，或者根据疲劳材料以及载荷的概率统计规律进行概率疲劳设计以及疲劳可靠性设计，或者按照断裂力学损伤容限法计算裂纹扩展寿命。Fe-safe疲劳计算技术先进，精度很高，广泛实用于各类金属、非金属以及合金等材料。总之，ANSYS后处理疲劳功能仅仅是Fe-safe疲劳功能的一个很少部分，Fe-safe作为复杂环境下的疲劳耐久性计算是ANSYS疲劳的补充与延伸。 问题2：什么是高周疲劳和低周疲劳？它们与应力疲劳法和应变疲劳法之间的关系是什么？ 回答2：根据疲劳断裂时交变载荷作用的总周次，疲劳可分为低周疲劳、中周疲劳和高周疲劳。一般将断裂时的总周次在以下时，称为低周疲劳；断裂时的总周次大于时，称为高周疲劳。在高周疲劳中，构件在破坏之前一般仅发生极小的弹性变形，而在低周疲劳中，应力往往大到足以使每个循环产生可观的宏观的塑性变形。因此，低周疲劳较高周疲劳而言显示出了延性状态。高周疲劳传统上用应力范围来描述疲劳破坏所需的时间或循环数，即按应力疲劳法评估疲劳寿命。低周疲劳（短寿命）传统上用应变范围来描述全塑性区域疲劳破坏所需的时间或循环数，即按(局部)应变疲劳法评估疲劳寿命。 ANSYS FE-SAFE是一款高级疲劳耐久性分析和信号处理的软件，它是多轴疲劳分析解决方案的领导者，算法先进，功能全面细致，是世界公认精度最高的疲劳分析软件。 ANSYS FE-SAFE既支持基于疲劳试验测试应力和应变信号的疲劳分析技术，也支持基于有限元分析计算的疲劳仿真设计技术。 ANSYS FE-SAFE具有完整的材料库、灵活多变的载荷谱定义方法、实用的疲劳信号采集与分析处理功能以及丰富先进的疲劳算法，完整的输出疲劳结果。 疲劳分析软件ANSYS FE_SAFE 简介（转） 来源：刘兴兴的日志
ABAQUS安装及汉化方法
统：Windows 7（32位系统）ABAQUS版本：6.9.3（DVD1为安装文件2.4G，DVD2为帮助文件1.8G）准备工作：1.由于安装文件为DVD格式，可下载并安装软件daemon_tools （DTLite4356-0091），直接打开DVD1,2 2.将License.dat用记事本打开，this_host改为本机系统：Windows 7（32位系统） 准备工作： 1.由于安装文件为DVD格式，可下载并安装软件daemon_tools （DTLite4356-0091），直接打开DVD1,2 2.将License.dat用记事本打开，this_host改为本机计算名（计算机属性，在“计算机名称、域或工作组设置”一栏找到“计算机全名”），27007不用改动 3.安装Microsoft Visual C++支持： 运行DVD1\win86_32\ 注：64位的机器请运行F:\ABAQUS6.9\win86_64文件夹下相应程序。 如果Microsoft Visual C++没有提前安装的话后边License会给以提示。 安装流程： 第一步：安装License 运行DVD1\ setup.exe \ （重要步骤）【右击install.exe—属性--兼容性—勾选“以兼容模式运行这个程序”—选择windows XP (service Pack 3)】。 选择License，一路Next直到出现需要输入HOSTNAME时，输入计算机全名，若已自动输入则Next，接着选择授权文件的安装类型，此处选择Just install the licensing utilities。 然后当有选择安装路径时自己选择想要的安装路径，然后Next直至完成。 安装完后将准备工作共的License.dat文件复制到安装盘（假定为C盘）C:\SIMULIA\License 目录。运行license utilities, 在config service中，service name: abaqus flexlm license server; 在“Path to the lmgrd.exe file”一栏中，选择指向“C:\SIMULIA\License\lmgrd.exe”在“Path to the license file”一栏中，选择指向“C:\SIMULIA\License\ABAQUS68_SUMMEREDITION.DA T”（第一步更改后的dat文件）在“Path to the debug log file”一栏中，选择指向“abaqus.log”（abaqus.log文件可以自己创建）Save service, 再start license。注意左下角出现start service successful. 第二步：安装product 兼容模式运行\ABAQUS6.9\win86_32\product\Windows\Disk1\InstData\VM\install.exe也可以在第一步的基础上选择product。 在需要输入Lisence server 1（REQUIRED）时，输入（27007@hostname），Server 2和Server 3可以不输入。 Next直至安装完成。 启动Abaqus CAE，先后看到命令提示符窗口和图形界面窗口，至此安装成功。 第三步：安装帮助文档 运行DVD2\ setup.exe \根据提示操作，在提示输入hostname/IP address时输入完整的计算机名称 然后当有选择安装路径时自己选择想要的安装路径，然后Next直至完成。 安装时license是关键，计算机名也很重要。 原文作者：houniao（转帖请注明作者）
疲劳分析步骤
现在要求对该轴进行疲劳分析。 使用WORKBENCH和DESIGNLIFE对之进行疲劳分析，分为两步。第一步是在WORKBENCH中建立有限元模型，并分别施加集中力和集中力偶，通过计算，得到两种情况的米塞斯应力，这相当于两种工况，这样可以得到ANSYS WORKBENCH的结构分析结果文件*.rst.第二步在DESIGNLIFE中进行，首先根据疲劳分析的五框图，构造疲劳分析流程，然后分别设定各个框图的属性，即有限元结果文件，载荷文件，材料文件，疲劳分析选项，然后启动分析，通过后处理以查看轴上各点的疲劳寿命。 1. WORKBENCH中建立有限元模型并进行分析。 （1）使用designmodeler创建几何模型。 （2）设置材料属性。 （3）划分网格。 （4）设置分析选项。 这里设置两个载荷步，其目的只是分开弯曲和扭转这两种工况。
（5）设置固定边界条件 （6）施加集中力和集中力偶。 第一个载荷步施加集中力，而第二个载荷步施加集中力偶。 （7）分析。 （8）得到两种情况的米塞斯应力。
左边的云图取自第一个载荷步，它是弯曲产生的应力云图。 右边的云图来自第二个载荷步，它是扭转产生的应力云图。 计算完毕后，保存结果，退出ANSYS WORKBENCH. 2. DESIGNLIFE中的疲劳分析。 （1）绘制疲劳分析流程图。 打开designlife，创建分析流程图如下。 该流程图中，左边时输入（左上是有限元结果输入，左下是载荷的时间历程曲线输入），中间是疲劳分析模块（这里是应变寿命疲劳分析），右边是输出（右上是有限元分析结果显示，右下是列表输出危险点的情况）。 （2）关联有限元分析结果文件
UM软件入门系列教程05：疲劳耐久性仿真-pub
目录 1．模块功能简介 (1) 2．柔性平台模型 (3) 2.1模型简介 (3) 2.2工作流程 (3) 2.3动力学计算 (4) 2.4应力载荷谱分析 (8) 2.4.1载荷工况描述 (9) 2.4.2初始化Sensor节点组 (15) 2.4.3设置应力载荷谱评估参数 (17) 2.4.4保存项目 (18) 2.4.5计算应力载荷时程 (19) 2.4.6应力载荷时程分析结果 (20) 2.5疲劳耐久性分析 (25) 2.5.1设置疲劳耐久性分析方法 (25) 2.5.2选择控制区域 (27) 2.5.3疲劳耐久性分析 (35) 2.5.4结果分析 (35)
1．模块功能简介 UM Durability模块是专业的疲劳耐久性CAE分析工具，它基于UM FEM 刚柔耦合动力学计算的结果进行应力载荷谱分析和疲劳寿命预测。其中，柔性体通过外部有限元软件导入（目前支持ANSYS和MSC.NASTRAN），刚柔耦合系统的动力学计算和疲劳后处理都在UM软件里完成。 首先，采用模态综合法将构件的柔性特性（包括模态振型和应力张量）从有限元软件导入UM，构成所需的刚柔耦合动力系统。其次，在UM里设置好一个或多个仿真工况，计算得到一系列有限元节点的应力时程数据。最后，根据材料的疲劳强度特性进行疲劳寿命预测。 疲劳耐久性分析有如下三个关键输入： ?应力载荷数据：节点应力时程； ?材料数据：材料在不同应力水平的循环载荷作用下的反应； ?疲劳耐久性分析方法。 由于从有限元软件导入UM的柔性体模型包含完整的单元和节点信息，根据模态综合法理论可以直接求得节点在任意时刻的位移和应力。只要选取足够的、合理的有限阶模态，就能快速地获得比较精确的响应。 在计算柔性体的弹性变形时采用模态叠加的方法，即可以通过一组模态振型的线性组合得到最终结果。显然，只需要乘以适当的系数，就能将这种方法拓展到应力的计算。这种系数，又称模态坐标，可以用来表征柔性体的瞬时应力状态。试想，在动力学计算的每一步，对每一个有限元节点都执行模态叠加计算，那么就可以获得整个时间历程上的节点位移和应力曲线。 使用UM FEM模块进行动力学计算时可以自动保存所有的模态坐标时程。UM Durability利用模态坐标时程数据和完整的节点信息（模态文件），可以快速获得每个节点的应力时程。然后，采用雨流计数法统计应力循环次数，最后根据S-N曲线等方法评估寿命。 仿真流程如图 1.1所示。
abaqus6.13安装方法
abaqus 6.13对操作系统的新要求： 自abaqus 6.13版本开始，将不再支持windows 的32位操作平台； 同时，也不再支持windows xp和windows vista操作系统； 安装： 1. Run "Install Abagus Product & Licensing" 2. In SIMULIA FLEXnet License Server window select "Just install the license utilities" NOTE: If you already have SIMULIA FLEXnet License Server for ABAQUS 6.12-3 installed and running you can use it for 6.13-1 too 3. After finishing License Utilities setup copy files "ABAQUS.lic" and "ABAQUS.log" to
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