Stainless Ferritic Steel

The ferritic stainless steel metallurgy has several advantages including its low cost option for corrosion resistant stainless steel, being appropriate for several automotive applications including Exhaust System Flanges and Hot Exhaust Gas Oxygen (HEGO) Sensor Bosses, its Antilock Brake System Sensor Rings as well as its Rearview Mirror Mounts. Magnetic applications for stainless steel include magnetic probes, sensors, armatures, and pole pieces requiring corrosion resistance without plating.

The following tables contain a list of the stainless steel, and other materials, that are available. For more complete coverage of properties, reference MPIF Standard 35, ASTM B783, ISO 5755, DIN 30910-4, and JIS Z2550, and download the technical information bulletins of interest. Standard powder metal materials, for sintering, are defined in North America by MPIF Standard 35 and ASTM B783, essentially equivalent standards. German PM steels are listed in DIN 30910-4, or more recently, ISO 5755. Japan steels are listed in JIS Z2550, with grade names changing with the revision from 1989 to 2000.

TYPE	GRADES	DESCRIPTION
409L	SSI-409L APMI/MPIF SS-409L, SS-409LE	A lean chromium (11%) stainless steel with a small columbium (niobium) addition to prevent weld sensitization.
410L	SSI-410L APMI/MPIF 410L ISO FL410 JIS SMS 2025, SMS 2035	A lean chromium (12%) stainless steel with low carbon and nitrogen (“L” indicates <0.03%) to maximize both corrosion resistance and ductility.
430L	SSI-430L APMI/MPIF 430L ISO FL430	A higher chromium (17%) stainless steel to improve general corrosion resistance compared to 409L and 410L.
430LCb	SSI-430LCb	Stainless steel 430L a type with a small columbium (niobium) addition to prevent weld sensitization.
430N	APMI/MPIF 430N2 DIN Sint-C42 (Type 430)	430 sintered in an atmosphere containing nitrogen for higher strength and hardness at the expense of some corrosion resistance.
434L	SSI-434L APMI/MPIF 434L ISO FL434	430L stainless steel with a small addition of molybdenum (1%) improves general corrosion resistance.
434LCb	SSI-434LCb APMI/MPIF 434LCb	434L with a small columbium (niobium) addition to prevent weld sensitization.
434N	APMI/MPIF 434N2	434 sintered in an atmosphere containing nitrogen for higher strength and hardness at the expense of some corrosion resistance.

Ferritic Stainless Steel – As-sintered

	Chemistry							Typical Properties
GRADE	Fe	C	N	Cr	Ni	Mo	Nb (Cb)	Density g/cm³	Tensile Strength ksi (MPa)	Yield Strength ksi (MPa)	Elongation %	Unnotched Impact Energy ft-lb (J)	Apparent Hardness HRB
SSI-409L-HTS	Bal	<0.03	<0.03	10.50-11.75	-	-	0.3-0.8	7.3	54 (370)	32 (220)	20	85 (115)	63
SS-410L-HTS SSI-410L-HTS	Bal	<0.03	<0.03	10.5-13.5	-	-	-	6.9 7.3	48 (330) 55 (380)	26 (180) 35 (240)	16 25	50 (68) -	45 59
SS-430L-HTS SSI-430L-HTS	Bal	<0.03	<0.03	16-18	-	-	-	7.1 7.3	50 (340) 58 (400)	26 (180) 35 (240)	20 20	80 (108) -	45 65
SSI-430LCb-HTS	Bal	<0.03	<0.03	16-18	-	-	0.3-0.8	7.3	59 (405)	37 (255)	16	-	70
SS-430N-HTS	Bal	<0.08	0.2-0.6	16-18	-	-	-	7.1	60 (410)	35 (240)	5	25 (34)	70
SS-434L-HTS SSI-434L-HTS	Bal	<0.03	<0.03	16-18	-	0.75-1.25	-	7.0 7.3	50 (340) 58 (400)	30 (210) 40 (275)	15 20	65 (88) 85 (115)	50 68
SSI-434LCb-HTS	Bal	<0.03	<0.03	16-18	-	0.75-1.25	0.3-0.8	7.3	62 (430)	40 (270)	18	-	70
SS-434N-HTS	Bal	<0.08	0.2-0.6	16-18	-	0.75-1.25	-	7.0	60 (410)	35 (240)	8	15 (20)	65

Density ranges for the stainless steel, and other materials listed are typically for single-pressed parts. Higher densities can be achieved with double-pressing. “HTS” indicates the material has been “high temperature sintered”, i.e. sintered at a minimum temperature of 2200 F (1200 C).