8407_2M_080722_Ed

ASSAB 8407 2M
uddeholM
oRVAR 2M

ASSAB 8407 2M
ReFeReNCe STANdARd AISI dF-2 dF-3 XW-5 XW-10 XW-41 XW-42 CARMo CAlMAX CAldIe ASSAB 88 ASP 23 ASP 30 ASP 60 VANAdIS 4 eXTRA VANAdIS 6 VANAdIS 10 VACRoN 40 618 618 hh 618 T 718 SuPReMe 718 hh NIMAX uNIMAX CoRRAX STAVAX eSR MIRRAX eSR PolMAX elMAX RAMAX lh RAMAX hh RoYAlloY PRodAX PT18 MMXl MM40 AlVAR 14 8407 2M 8407 SuPReMe dIeVAR hoTVAR QRo 90 SuPReMe 705 709 760 MoldMAX SC MoldMAX Xl MoldMAX hh AlVAR 14 oRVAR 2M oRVAR SuPReMe dIeVAR hoTVAR QRo 90 SuPReMe 4340 4140 1050 1.6582 1.7225 1.1730 SNCM8 SCM4 S50C h13 h13 Premium 1.2714 1.2344 1.2344 eSR SKT 4 SKd 61 SKd 61 IMPAX SuPReMe IMPAX hh NIMAX uNIMAX CoRRAX STAVAX eSR MIRRAX eSR PolMAX elMAX RAMAX lh RAMAX hh 420 F Mod. 420 F Mod. 420 Mod. 420 Mod. 1.2083 eSR SuS 420J2 CARMo CAlMAX CAldIe SleIPNeR VANAdIS 23 VANAdIS 30 VANAdIS 60 VANAdIS 4 eXTRA VANAdIS 6 VANAdIS 10 VANCRoN 40 P20 Mod. P20 Mod. P20 Mod. P20 Mod. P20 Mod. 1.2738 1.2738 1.2738 Mod. 1.2738 1.2738 (M3:2) M3:2 + Co 1.3344 1.3244 1.3241 SKh 53 SKh 40 SVeRKeR 3 RIGoR SVeRKeR 21 ARNe o1 o1 d6 (d3) A2 d2 d2 dIN 1.2510 1.2510 (1.2436) 1.2363 1.2379 1.2379 JIS SKS 3 SKS 3 (SKd 2) SKd 12 SKd 11 SKd 11
This information is based on our present state of knowledge and is intended to provide general notes on our products and their uses. It should not therefore be construed as a warranty of specific properties of the products described or a warranty for fitness for a particular purpose. Edition 080722
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ASSAB 8407 2M
General
8407 2M is a chromium-molybdenum-vanadium-alloyed steel which is characterised by: Good resistance to abrasion at both low and high temperatures High level of toughness and ductility Uniform and high level of machinability and polishability Good high-temperature strength and resistance to thermal fatigue Excellent through-hardening properties Very limited distortion during hardening
Applications
PlASTIC MouldING
Part Injection moulds Compression/ transfer moulds Aust. and tempering temp. Austenitising 1020-1030°C Tempering 250°C HRC 50-52
eXTRuSIoN
Aluminium, magnesium alloys, HRC 44-50 Copper alloys HRC 43-47 Stainless steels HRC 45-50
Part Typical analysis % Standard specification Delivery condition Colour code C 0.39 Si 1.0 Mn 0.4 Cr 5.3 Mo 1.3 V 0.9 Dies Backers, die holders, liners, dummy blocks, stems Austenitising temperature
AISI H13, WNr. 1.2344, SKD 61, EN X40CrMoV5-1 Soft annealed to approx. 185 HB Orange / Violet
41-50
40-48
40-48
1020– 1030°C
1040–1050°C
Stem
Dummy Block
Liner
Intermediate Liner
Mantle
Die
Extrusion tooling components.
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ASSAB 8407 2M
Properties
PhYSICAl dATA Unless otherwise indicated, all specimens were hardened 30 minutes at 1025°C, quenched in air and tempered 2 + 2 h at 610°C. The hardness were 45 ± 1 HRC.
Temperature Density kg/m3 Modulus of elasticity MPa Coefficient of thermal expansion per °C from 20°C Thermal conductivity W/m °C
20°C
400°C
600°C
7800
7700
7600
210 000
180 000
140 000
-
12.6 x 10 -6
13.2 x 10 -6
25
29
30
MeChANICAl PRoPeRTIeS
Aluminium extrusion profiles.
Approximate tensile strength at room temperature.
Hardness Tensile strength, Rm Yield strength, RP0.2 52 HRC 1820 MPa 1520 MPa 45 HRC 1420 MPa 1280 MPa
oTheR APPlICATIoNS
Application Severe cold punching, scrap shears Hot Shearing Shrink rings (e.g., for cemented carbide dies) Wear resisting parts Aust. and tempering temp. Austenitising 1020-1030°C Tempering 250°C Austenitising 1020-1030°C Tempering 250°C Tempering 575-600°C Austenitising 1020-1030°C Tempering 575-600°C Austenitising 1020-1030°C Tempering 575°C Nitriding HRC 50-52
Approximate strength at elevated temperatures Longitudinal direction.
Rm, Rp0.2 MPa 2000 1800 1600 1400 1200 1000 Rm Rp0.2 800 600 400 200 0
A5, Z% 100 90 80 70 60 50 40 30 20 10 100 200 300 400 500 600 700oC
50-52 45-50 45-50 Core 50-52 Surface ~1000HV1
For applications requiring extreme levels of toughness and ductility, e.g., die casting dies, forging dies, the premium grade H13 steel, 8407 Supreme, is recommended.
Testing temperature
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ASSAB 8407 2M
Heat treatment
SoFT ANNeAlING Protect the steel and heat through to 850°C. Then cool in the furnace at 10°C per hour to 650°C, then freely in air. QueNChING MedIA High speed gas/circulating atmosphere Vacuum (high speed gas with sufficient positive pressure). Interrupted quench is recommended for distortion control, or when quench cracking is a concern. Martempering bath or fluidised bed at 450–550°C, then cool in air Martempering bath or fluidised bed at approx. 180–220°C then cool in air Warm oil Note 1: Temper the tool as soon as its temperature reaches 50–70°C. hARdeNING Preheating temperature: 600–850°C, normally in two preheating steps. Austenitising temperature: 1020–1050°C, normally 1020°–1030°C. Temperature °C 1025 1050 Soaking time minutes 30 15 Hardness before tempering 53±2 HRC 54±2 HRC Note 2: In order to obtain the optimum properties for the tool, the cooling rate should be fast, but not at a level that gives excessive distortion or cracks. TeMPeRING Choose the tempering temperature according to the hardness required by reference to the tempering graph. Temper at least twice with intermediate cooling to room temperature. The lowest tempering temperature which should be used is 180°C. The minimum holding time at tempering temperature is 2 hours. To avoid “temper brittleness”, do not temper in the range 425–550°C, see graph. Tempering graph
Hardness, HRC 60 55 Austenitising temp. 1050oC Retained austenite %
STReSS RelIeVING After rough machining, the tool should be heated through to 650°C, holding time 2 hours. Cool slowly to 500°C, then freely in air.
Soaking time = time at hardening temperature after the tool is fully heated through. Protect the tool against decarburisation and oxidation during hardening. hardness, grain size and retained austenite as functions of austenitising temperature
Grain Hardness Size ASTM HRC 60 10 8 54 6 4 52 50 48 46 44 42 40 1000 1020 1040 Retained austenite 6 4 2 1060oC 58 56 Hardness Grain Size
50 Retained austenite %
1020oC
1025oC Temper brittleness zone
45 6 Retained austenite 35 4
40
30 25 100 200 300 400 500 600
2
700oC
Tempering temperture (2h + 2h)
Tempering within the range 425–550°C is normally not recommended due to the reduction in toughness properties.
Austenitising temperture
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ASSAB 8407 2M
effect of time at tempering temperature
Hardness, HRC 58 54 50 46 42 38 34 30 1 1.5 2.5 4 6.5 10 15 25 40 65 100 400 Total holding time at tempering temperture, hours Austenitizing temperture 1020oC 600oC 550oC Air hardened from 1020°C Vacuum hardened from 1020°C Min. Max. Min. Max. -0.02 +0.03 +0.01 +0.02 -0.05 +0.02 -0.02 -0.04 ±0 +0.05 +0.08 +0.12 500oC Oil hardened from 1020°C Min. Max.
dIMeNSIoNAl ChANGeS duRING hARdeNING Specimen size: 100 x 100 x 25 mm.
Width % -0.08 -0.15 Length % -0.06 -0.16 Thickness % ±0 +0.03
dIMeNSIoNAl ChANGeS duRING TeMPeRING
Dimensional change % +0.12 +0.08 +0.04 0 -0.04 -0.08 -0.12 100 200 300 400 500 Tempering temperture (1h + 1h) 600 700oC
Note: The dimensional changes in hardening and tempering should be added. CCT graph Austenitising temperature 1025°C. Holding time 30 minutes.
°C 1100 1000 900 800 700 600 500 400 300 200 100 Mf 1
1 2
Cooling Hardness Curve No. HV 10 T800-500 (sec)
Austenitising temperature 1025oC Holding time 30 minutes AC = 940oC
3
AC = 840oC
1
Carbides
Pearlite
MS
Bainite
Martensite
3 4 5 6 7 8 9 10
1 2 3 4 5 6 7 8 9 10
707 673 613 613 599 592 560 519 483 222
1 6 105 316 527 1054 2772 5271 7944 20768
10 1
100 10
1000
10 000 100 1 10 90
100 000 1000
Seconds Minutes 100 Hours
0.2
1.5
10
600
Air cooling of bars, ?mm
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ASSAB 8407 2M
Machining recommendations
The cutting data below are to be considered as guiding values and as starting points for developing your own best practice. Condition: Soft annealed condition ~185 hB TuRNING
Turning with carbide Rough turning 200 - 250 Fine turning 250 - 300 Turning with HSS? Fine turning 25 - 30 Depth of cut (ap) mm 0.2 - 0.4 2-4 P20 - P30 Coated carbide 0.05 - 0.2 0.5 - 2 P10 Coated carbide or cermet 0.05 - 0.3 0.5 - 3 Carbide designation ISO P20 - P40 Coated carbide P10 - P20 Coated carbide or cermet 2-5 ≤2 Cutting data parameters
MIllING Face and square shoulder milling
Milling with carbide Rough milling Fine milling
Cutting data parameters
Cutting speed (vc) m/min Feed (f z) mm/tooth
180 - 260
260 - 300
Cutting speed (vc) m/min Feed (f) mm/r Depth of cut (ap) mm Carbide designation ISO
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0.2 - 0.4
0.1 - 0.2
-
end milling
Type of milling Cutting data parameters Solid carbide Carbide indexable insert High speed steel
High speed steel
dRIllING high speed steel twist drill
Drill diameter mm ≤5 5 - 10 10 - 15 15 - 20 Cutting speed (vc) m/min 16 - 18 * 16 - 18 * 16 - 18
*
Cutting speed (vc) m/min Feed (f) mm/r 0.05 - 0.15 0.15 - 0.20 0.20 - 0.25 0.25 - 0.35
1 2
160 - 200
170 - 230
35 - 401
Feed (f) mm/tooth Carbide designation ISO
0.03 - 0.202
0.08 - 0.202
0.05 - 0.352
-
P20 - P30
-
16 - 18 *
For coated HSS end mill, vc~ 55–60 m/min Depending on radial depth of cut and cutter diameter
* For coated HSS drill, vc~ 28–30 m/min
GRINdING Wheel recommendation
Carbide drill
Type of grinding Type of drill Cutting data parameters Face grinding straight wheel Indexable insert Solid carbide Brazed carbide1 Face grinding segments Cylindrical grinding Internal grinding Feed (f) mm/r
1 2
Soft annealed condition A 46 HV A 24 GV A 46 LV A 46 JV A 100 LV
Hardened condition A 46 HV A 36 GV A 60 KV A 60 IV A 120 KV
Cutting speed (vc) m/min
220 - 240
130 - 160
80 - 110
0.03 - 0.102
0.10 - 0.252
0.15 - 0.252
Profile grinding
Drill with interntal cooling channels and brazed carbide tip Depending on drill diameter
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ASSAB 8407 2M
Surface treatment
NITRIdING ANd NITRoCARBuRISING Nitriding and nitrocarburising result in a hard surface layer which is very resistant to wear and erosion. The nitrided layer is, however, brittle and may crack or spall when exposed to mechanical or thermal shock, the risk increasing with layer thickness. Before nitriding, the tool should be hardened and tempered at a temperature at least 25–50°C above the nitriding temperature. Nitriding in ammonia gas at 510°C, or plasma nitriding in a 75% hydrogen/25% nitrogen mixture at 480°C, both result in a surface hardness of about 1100 HV0.2 . In general, plasma nitriding is the preferred method because of better control over nitrogen potential. Particularly, plasma nitriding can readily avoid the formation of socalled white layer, which is not recommended for hot work service. However, careful gas nitriding can give perfectly acceptable results. 8407 2M can also be nitrocarburised in either gas or salt bath. The surface hardness after nitrocarburising is 900–1000 HV0.2 .
Electrical discharge machining
If spark-erosion is performed in the hardened and tempered condition, the white re-cast layer should be removed mechanically by grinding or stoning. The tool should then be given an additional temper at approx. 25°C below the previous tempering temperature.
Welding
Welding of tool steel can be performed with good results if proper precautions are taken regarding elevated temperature, joint preparation, choice of consumables and welding procedure. The following guidelines summarise the most important welding process parameters. For more detailed information, refer to ASSAB brochure “Welding of Tool Steel”.
Welding method Working temp. Filler material
depth of nitriding
Time h 10 30 10 30 Depth mm 0.12 0.20 0.12 0.18
Process Gas nitriding at 510°C Plasma nitriding at 480°C Nitrocarburising – in gas at 580°C – in salt bath at 580°C
TIG
MMA
325 - 375oC QRO 90 TIG-WELD DIEVAR TIG-WELD
325 - 375oC
QRO 90 WELD
2.5 1
0.11 0.06 Cooling rate Hardness after welding 20 - 40oC/h for the first 2 to 3 hours and then freely in air
Nitriding to case depths >0.3 mm is not recommended for hot work applications. 8407 2M can be nitrided in the soft annealed condition. The hardness and depth of case will, however, be reduced somewhat in this case.
50 - 55 HRC
50 - 55 HRC
heat treatment after welding Hardened condition Temper at 25°C below the original tempering temperature. Soft anneal the material at 850°C in protected atmosphere. Then cool in the furnace at 10°C per hour to 650°C, then freely in air.
hARd ChRoMe PlATING After plating, parts should be tempered at 180°C for 4 hours, within 4 hours of plating, to avoid the risk of hydrogen embrittlement.
Soft annealed condition
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ASSAB 8407 2M
Polishing
8407 2M exhibits good polishability in the hardened and tempered condition. Polishing after grinding can be effected using aluminium oxide or diamond paste. TYPICAl PRoCeduRe 1. Rough grinding to 180–320 grain size using a wheel or stone. 2. Fine grinding with abrasive paper or powder, down to 400–800 grain size. 3. Polish with diamond paste grade 15 (15μm grain size) using a polishing tool of soft wood or fibre. 4. Polish with diamond paste 8–6–3 (8–6–3μm grain size) using a polishing tool of soft wood or fibre. 5. When demands on surface finish are high, grade 1 (1μm grain size) diamond paste can be used for final polishing with a fibre polishing pad.
Photo-etching
8407 2M is particularly suitable for texturing by the photo-etching method. Its high level of homogeneity and low sulphur content ensures accurate and consistent pattern reproduction.
Further information
For further information, i.e., steel selection, heat treatment, application and availability, please contact our ASSAB office* nearest to you. *See back cover page
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ASSAB 8407 2M
Relative comparison of ASSAB hot work die steels
QuAlITATIVe CoMPARISoN oF CRITICAl dIe STeel PRoPeRTIeS
Temper resistance Hot yield strength Creep strength Coefficient of thermal expansion Heat conductivity
ASSAB grade ALVAR 14 8407 2M 8407 SUPREME DIEVAR HOTVAR QRO 90 SUPREME
Ductility
QuAlITATIVe CoMPARISoN oF ReSISTANCe To dIFFeReNT dIe FAIluReS
ASSAB grade ALVAR 14 8407 2M 8407 SUPREME DIEVAR HOTVAR QRO 90 SUPREME Heat checking Gross cracking Hot wear / Erosion Plastic deformation Corrosion (Al)
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ASSAB 8407 2M
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ASSAB TOOL STEELS have been in Asia since 1945. Our customers associate ASSAB brand with tooling materials that are high in quality and consistency. The ASSAB sales companies and distributors offer you well assorted stocks in a number of places covering the Asia Pacific region. To further shorten the lead time, ASSAB will mill, grind, drill and even wire-cut the tool steel to meet your requirements. ASSAB also provides state-of-the-art vacuum heat treatment services to enhance the steel properties. Our engineers and metallurgists are always ready to assist you in your choice of the optimum steel grade and the best treament for each application. We always carry out material examinations at our local mini laboratories and at the central laboratory in Sweden. Our steel mill in Sweden, Uddeholm Tooling, is one of the few steelworks in the world that is dedicated to the manufacture of tool steels only. Uddeholm Tooling is certified to ISO 9001 and ISO 14001.
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Qingdao ASSAB Tooling (Qingdao) Co., Ltd.
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Our forging press is one of the most modern of its kind in the world.
Besides tool steels, the ASSAB services for tool makers include:
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Welding electrodes for repair welding of tools High strength aluminium for tooling purposes Copper alloys (e.g., beryllium copper) for inserts in moulds Alloy machinery steels Cold rolled strip steels for saws, compressor valves, coater blades, etc. High Performance Steels (HPS)
Sales office only
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Granshot