634 S35500 - ASTM A705/A705M-2023

Grade	634
USA UNS	S35500
Corresponding Standard	ASTM A705/A705M-2023 Standard Specification for Age-Hardening Stainless Steel Forgings
Classification	Precipitation-Hardening Stainless Steel

634 Chemical Element Composition Content (%)

Component	C	Si	Mn	P	S	Cr	Ni	Mo	N
Minimum Value	0.1	-	0.5	-	-	15	4	2.5	0.07
Maximum Value	0.15	0.5	1.25	0.04	0.03	16	5	3.25	0.13

634 Mechanical Properties

	Mark	Heat Treatment or Condition	Tensile Strength σ_b Mpa	Yield Point σ_s Mpa	Elongation or Extension Rate δ %	Reduction of Area ψ %	Hardness HBW
		Solution Treatment: 1040±15 °C（quench, hold not less than 3 h at -100 °F or lower），②					≤363
	H1000	Hardening or Aging Treatment, ③	≥1170	≥1070	≥12	≥25	HRC: ≥37 HB: ≥341

* （L）：Longitudinal；（T）：Transverse。

① Either Rockwell C hardness or Brinell is permissible. On sizes of 12.70 mm and smaller, Rockwell C is preferred.
② Equalization and over-tempering treatment 775 ± 30 °C for not less than 3 h, cool to room temperature, heat to 580 ± 15°C for not less than 3 h.
③ 955 for not less than 10 min, but not more than 1 h. Water quench. Cool to not higher than minus 75 °C. Hold for not less than 3 h. Temper at 540 °C, holding for not less than 3 h.

634 Corresponding Standards(Same grade name, different standards)

1	ASTM A564/A564M-2019(a)
	634 S35500
2	ASTM A693-2013
	634 S35500
3	ASTM A959-2019
	634 S35500
4	ASTM A705/A705M-2023
	634 S35500

Note: The data is for reference only! If you have any questions, please fill out "I want to correct it"!