Page 1662 - MiSUMi 2025

[Materials]
Varieties and Applications 1

1.General Steel Materials
Type Material JIS Symbol Material GB Symbol Applications Comment GB Flat Bar Square Bar Hexagonal Bar Round Bar Steel Plate Section Steel
Rolled Steel for General Fine Workability and
General Structure SS400 Q235 Machine Parts Weldability GB/T 700-2006 k k k k k
Polished General Excellent Precision and Surface
Steel Bar SS400D － Machine Parts Roughness. Ready for use － k k k k
(Cold-Drawn) directly after slight cutting.
Carbon Steel S45C 45 Steel Fit for Hardening
for General Tensile Strength 58kgf/mm 2 GB/T 699-2015
Machine Machine Parts Fit for Hardening k k k k k
Structural Use S50C 50 Steel Tensile Strength 66kgf/mm 2
For Drill Rod (Round Bar)
SKS93 － SK4 surface-finished after － k k k
Carbon Tool Shafts, Pins, cold drawing.
Steel etc. Class 7 (−DG7)=h7
SK4 T11 Class 8 (−DG8)=h8 k k
Class 9 (−DG9)=h9.
GB/T 1299-2014
SK5 T8Mn Deformation caused by k k k
Alloy Tool Hardening Hardening
Steel Parts is much less than that of SK
SKS3 9CrWMn material. － k k k
SCM435 35CrMo General Tensile Strength 70kgf/mm , GB/T 3077-2015
2
Chrome machine Parts Tensile Strength after Hardening
Molybdenum SCM415 － requiring & tempering: 95 kgf/mm or － k k k k k
2
Steel strength. more. Hardness: HB270 or more.
SCM420 20CrMo Screws, etc. Hardening: HRC50 or more. －
Sulfuric and SUM21 Y12 Made of carbon steel plus GB/T 8731-2008
Sulfur General sulfur to enhance machinability.
Compound SUM22L Machine Parts
Free － (Free-Cutting Free-Cutting Steel － k k k
Cutting steel) containing sulfur and lead.
Steel SUM24L Y15Pb GB/T 8731-2008
High Carbon Chrome SUJ2 GCr15 Roller Bearing Steel GB/T 18254-2016
Bearing Steel bearings, etc. k
Rolled at an almost ambient temperature.
Cold-Rolled Covers, High dimensional precision and fair texture.
Steel Plate SPCC － cases, etc. Fine machinability. Easy to － k
bend, wring and cut.
Fine Weldability.
Hot-Rolled General machine Plates for general use are
Steel Plate SPHC － structural parts. 6 mm or less in thickness. － k
2. Stainless Steel Materials
Type Material JIS Symbol Material GB Symbol Applications Comment Magnetism GB Flat Bar Square Bar Hexagonal Bar Round Bar Steel Plate Section Steel
Austenite SUS303 Y1Cr18Ni9 Machine parts 18-8 Free-Cutting Stainless Steel, Non- None* GB/T 1220-2007 k k
requiring antirusting Magnetic. More Machinable than SUS304
Austenite SUS304 06Cr19Ni10 Machine parts Most Versatile Antirusting and Heat- None* GB/T 3280-2015 k k k k k k
requiring antirusting Resisting Steel for General Use
Austenite SUS316 0Cr17Ni12Mo2 Machine parts More resisting to seawater and other None* GB/T 1220-2007 k k k
requiring antirusting media than SUS304.
Martensite SUS440C － Machine parts requiring antirusting Fit for Hardening. Available － k
(Less corrosion resistant than austenite.)
Martensite SUS410 1Cr17 Machine parts requiring antirusting Fit for Hardening. Fine Available GB/T 1220-2007 k
(Less corrosion resistant than austenite.) Machinability.
*EMartensite exhibits magnetic properties. Machining of Austenite may cause magnetic properties.

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