ASTM F738M

ASTM F738M Screws Bolts & Studs Specification

Stainless Steel Metric Bolts Screws & studs for use in engineering applications requiring general corrosion resistance

Overview

High-Quality Stainless Steel Bolts, Screws, and Studs by Adfast Component LTD

Adfast Component LTD proudly offers stainless steel metric bolts, screws, and studs that meet the stringent ASTM F738 / F738M specifications. Designed for engineering applications requiring general corrosion resistance, our products cater to a wide range of industrial needs with nominal thread diameters ranging from M1.6 to M36. We provide eight groups of stainless steel alloys, including austenitic (Grades A1, A2, A4), ferritic (Grade F1), martensitic (Grades C1, C3, C4), and precipitation hardening (Grade P1), ensuring top-notch performance and durability.

Our product range adheres to ISO 3506 standards, covering twenty property classes for superior reliability. Additionally, Adfast Component LTD offers exclusive non-ISO property classes like C1-110, C4-110, C3-120, and P1-90, ideal for specialized applications. For larger thread diameters (above M20), we provide property classes A1-70, A2-70, A4-70, A1-80, A2-80, and A4-80. Complement your projects with compatible nuts under Specification F836M. Trust Adfast for unparalleled quality and compliance in stainless steel fasteners.

Related Specifications

Property Classes

Property Class	Permissible Alloys
A1-50	304, 304L, 305^A
A1-70	384, 18-9LW, 302HQ
A1-80	…
A2-50	…
A2-70	321, 347
A2-80	…
A4-50	…
A4-70	316, 316L
A4-80	…
F1-45	430^B
C1-70	410
C1-110	…
C3-80	431
C3-120	…
C4-70	416, 416Se
C4-110	…
P1-90	630
(A) When approved by the purchaser, Alloys 303, 303Se, or XM1 may be furnished. (B) When approved by the purchaser, Alloy 430F may be furnished.

Chemical Composition

Alloy Group	Alloy	UNS Designation	C	Mn	P	S	Si	Cr	Ni	Cu	Mo	Others
A1	303	S30300	0.15	2.00	0.20	0.15 min	1.00	17.0 to 19.0	8.0 to 10.0	…	0.60 max^A	…
A1	303Se	S30323	0.15	2.00	0.20	0.060	1.00	17.0 to 19.0	8.0 to 10.0	…	…	Se 0.15 min
A1	304	S30400	0.08	2.00	0.045	0.030	1.00	18.0 to 20.0	8.0 to 10.5	1.00		…
A1	304L	S30403	0.03	2.00	0.045	0.030	1.00	18.0 to 20.0	8.0 to 12.0	1.00		…
A1	305	S30500	0.12	2.00	0.045	0.030	1.00	17.0 to 19.0	10.5 to 13.0	1.00		…
A1	384	S38400	0.08	2.00	0.045	0.030	1.00	15.0 to 17.0	17.0 to 19.0			…
A1	XM1	S20300	0.08	5.0 to 6.5	0.040	0.18 to 0.35	1.00	16.0 to 18.0	5.0 to 6.5	1.75 to 2.25	0.50 max^A	…
A1	18-9LW	S30430	0.10	2.00	0.045	0.030	1.00	17.0 to 19.0	8.0 to 10.0	3.0 to 4.0	…	…
A1	302HQ	S30433	0.03	2.00	0.045	0.030	1.00	17.0 to 19.0	8.0 to 10.0	3.0 to 4.0	…	…
A4	316	S31600	0.08	2.00	0.045	0.030	1.00	16.0 to 18.0	10.0 to 14.0	…	2.00-3.00	…
A4	316L	S31603	0.03	2.00	0.045	0.030	1.00	16.0 to 18.0	10.0 to 14.0	…	2.00-3.00	…
A2^†	321	S32100	0.08	2.00	0.045	0.030	1.00	17.0 to 19.0	9.0 to 12.0	…	…	Ti 5 × C min
A2	347	S34700	0.08	2.00	0.045	0.030	1.00	17.0 to 19.0	9.0 to 13.0	…	…	Cb + Ta 10 × C min
F1	430	S43000	0.12	1.00	0.040	0.030	1.00	16.0 to 18.0	…	…		…
F1	430F	S43020	0.12	1.25	0.060	0.15 min	1.00	16.0 to 18.0	…	…	0.60 max^A	…
C1	410	S41000	0.15	1.00	0.040	0.030	1.00	11.5 to 13.5	…	…	…	…
C4	416 416Se	S41600	0.15	1.25	0.060	0.15 min	1.00	12.0 to 14.0	…	…	0.60 max^A	Se 0.15 min
C4	…	S41623	0.15	1.25	0.060	0.060	1.00	12.0 to 14.0	…	…	…	…
C3	431	S43100	0.20	1.00	0.040	0.030	1.00	15.0 to 17.0	1.25 to 2.50	…	…	…
P1	630	S17400	0.07	1.00	0.040	0.030	1.00	15.0 to 17.5	3.0 to 5.0	3.0 to 5.0	…	Cb + Ta 0.15-0.45
(A) At manufacturer’s option, determined only when intentionally added.

Mechanical Requirements

Property Class	Condition	Alloy Mechanical Property Marking	Nominal Thread Diameter	Product Length	Full Size Product Tests				Machined Specimen Tests			Hardness
					Tensile Strength,MPa C	Yield Strength,MPa C,D	Exten-sion E	Torsional Strength F	Tensile Strength,MPa	Yield Strength,MPa	Elonga-gation,%	Vickers		Rockwell
					min	min	min	min	min	min	min	min	max	min	max
A1-50	AF	F738A	M1.6±M5	all	500	. . .	. . .	Table 6	. . .	. . .	. . .	. . .	165	. . .	B85
A2-50		F738B	M6±M36	all	500	210	0.6D	. . .	500	210	30	. . .	165	. . .	B85
A4-50		F738C	. . .	. . .	. . .	. . .	. . .	. . .	. . .	. . .	. . .	. . .	. . .	. . .	. . .
A1-70		F738D	M1.6±M5	8D	700	. . .	. . .	Table 6	. . .	. . .	. . .	220	330	B96	C33
A2-70	CW	F738E	M6±M20	8D	700	450	0.4D	. . .	650	400	20	220	330	B96	C33
A4-70		F 738F	over M20±M36	8D	550	300	0.2Dx	. . .	520	270	25	160	310	B83	C31
A4-70		F 738F	M1.6±M5	8D	800	. . .	. . .	Table 6	. . .	. . .	. . .	240	350	C23	C36
A1-80	SH	F738G	M6±M20	8D	800	600	0.3D	. . .	780	600	12	240	350	C23	C36
A2-80		F738H	over M20±M24	8D	700	500	0.2D	. . .	680	480	15	220	330	B96	C33
A4-80		F 738J	over M24±M30	8D	650	400	0.2D	. . .	620	370	20	200	310	B93	C30
A4-80		F 738J	over M30±M36	8D	600	300	0.2D	. . .	570	270	28	180	285	B89	C28
F1-45	AF	F 738K	M1.6±M5	all	450	. . .	. . .	. . .	. . .	. . .	. . .	. . .	165	. . .	B85
F1-45	AF	F 738K	M6±M36	all	450	250	0.2D	. . .	450	250	25	. . .	165	. . .	B85
F1-60	CW	F 738L	M1.6±M5	8D	600	. . .	. . .	. . .	. . .	. . .	. . .	180	285	B89	C28
F1-60	CW	F 738L	M6±M36	8D	600	410	0.2D	. . .	550	360	20	180	285	B89	C28
C1-50	A	F738M	M1.6±M5	all	500	. . .	. . .	. . .	. . .	. . .	. . .	. . .	165	. . .	B85
C4-50	A	F738N	M6±M36	all	500	250	0.2D	. . .	500	250	20	. . .	165	. . .	B85
C1-70	H	F738P	M1.6±M5	all	700	. . .	. . .	. . .	. . .	. . .	. . .	220	330	B96	C34
C4-70	H	F738R	M6±M36	all	700	410	0.2D	. . .	700	410	18	220	330	B96	C34
C1-110	HT	F738S	M1.6±M5	all	1100	. . .	. . .	. . .	. . .	. . .	. . .	350	440	C36	C45
C4-110	HT	F738T	M6±M36	all	1100	820	0.2D	. . .	1100	820	12	350	440	C36	C45
C3-80	H	F 738U	M1.6±M5	all	800	. . .	. . .	. . .	. . .	. . .	. . .	240	340	C23	C35
C3-80	H	F 738U	M6±M36	all	800	640	0.2D	. . .	800	640	15	240	340	C23	C35
C3-120	HT	F 738V	M1.6±M5	all	1200	. . .	. . .	. . .	. . .	. . .	. . .	380	480	C39	C48
C3-120	HT	F 738V	M6±M36	all	1200	950	0.2D	. . .	1200	950	10	380	480	C39	C48
P1-90	AH	F 738W	M1.6±M5	all	900	. . .	. . .	. . .	. . .	. . .	. . .	285	370	C28	C38
P1-90	AH	F 738W	M6±M36	all	900	700	0.2D	. . .	900	700	16	285	370	C28	C38
(A) Legend of Conditions: AF-formed and annealed. CW-formed from annealed stock, thus acquiring a degree of cold work. SH-machined from strain hardened stock. A-machined from annealed or solution annealed stock, thus retaining the properties of the original material, or hot formed and solution annealed. H-hardened and tempered at 565°C medium. HT-hardened and tempered at 275°C minimum. AH-solution annealed and age hardened after forming. (B) For product lengths: ªallº means all lengths ^ª8D º means 8 times nominal diameter maximum. (C) Tensile strength and yield strength values for full-size products of each property class are given in table on yield and tensile strength. (D) Yield strength is the stress at which an offset of 0.2 % gage lingth occurs. (E) Extension measurement is determined in accordance with the test procedure speci®ed in 10.2.3. (F) Torsional strength requirements apply only to austenitic steel fasteners with nominal thread diameters M5 and smaller. Values are given in table on torsional strength.

Yield and Tensile Strength
Values for Length
Torsional Strength

Nominal Size and Thread Pitch	Stress Area,^A mm²	Yield or Tensile Stress, MPa
Nominal Size and Thread Pitch	Stress Area,^A mm²	210	250	300	400	410	450	500	550	600	640	650	700	800	820	900	950	1100	1200
M1.6 3 0.35	1.27	…	…	…	…	…	0.57	0.64	…	0.76	…	…	0.89	1.02	…	…	…	1.4	1.52
M2 3 0.4	2.07	…	…	…	…	…	0.93	1.04	…	1.24	…	…	1.45	1.66	…	…	…	2.28	2.48
M2.5 3 0.45	3.39	…	…	…	…	…	1.52	1.7	…	2.03	…	…	2.37	2.71	…	…	…	3.73	4.07
M3 3 0.5	5.03	…	…	…	…	…	2.26	2.52	…	3.02	…	…	3.52	4.02	…	…	…	5.53	6.04
M4 3 0.7	8.78	…	…	…	…	…	3.95	4.39	…	5.27	…	…	6.15	7.02	…	…	…	9.66	10.5
M5 3 0.8	14.2	…	…	…	…	…	6.39	7.1	…	8.52	…	…	9.94	11.4	…	…	…	15.6	17
M6 3 1	20.1	4.22	5.03	6.03	8.04	8.24	9.05	10.1	11.1	12.1	12.9	13.1	14.1	16.1	16.5	18.1	19.1	22.1	24.1
M8 3 1.25	36.6	7.69	9.15	11	14.6	15	16.5	18.3	20.1	22	23.4	23.8	25.6	29.3	30	32.9	34.8	40.3	43.9
M10 3 1.5	58	12.2	14.5	17.4	23.2	23.8	26.1	29	31.9	34.8	37.1	37.7	40.6	46.4	47.6	52.2	55.1	63.8	69.6
M12 3 1.75	84.3	17.7	21.1	25.3	33.7	34.6	37.9	42.2	46.4	50.6	54	54.8	59	67.4	69.1	75.9	80.1	92.7	101
M16 3 2	157	33	39.3	47.1	62.8	64.4	70.7	78.5	86.4	94.2	100	102	110	126	129	141	149	173	188
M20 3 2.5	245	51.5	61.3	73.5	98	100	110	123	135	147	157	159	172	196	201	221	233	270	294
M24 3 3	353	74.1	88.3	106	141	145	159	177	194	212	226	229	247	282	289	318	335	388	424
M30 3 3.5	561	118	140	168	224	230	252	281	309	337	359	365	393	449	460	505	533	617	673
M36 3 4	817	172	204	245	327	335	368	409	449	490	523	531	572	654	670	735	776	899	980
^A Stress area = 0.7854 ( D − 0.9382 P)² where: D = nominal size, mm, and P = thread pitch, mm

Nominal Thread Diameter	x, mm
M1.6	4
M2	5
M2.5	6
M3	8
M4	10
M5	12
M6	14
M8	20
M10	25
M12	30
M16	40
M20	45
M24 and larger	3D
(A) x equals the minimum length of product subject to tension testing.

0.63 Nominal Size and Thread Pitch	Torsional Strength, min − Grades A1, A2, A4
	Class 50	Class 70	Class 80
	N´m	N´m	N´m
M1.6 3 0.35	0.15	0.20	0.27
M2 3 0.4	0.30	0.40	0.56
M2.5 3 0.45	0.60	0.90	1.20
M3 3 0.5	1.10	1.60	2.10
M3.5 3 0.6	1.80	2.50	3.20
M4 3 0.7	2.70	3.80	4.90
M5 3 0.8	5.50	7.80	10.00
(A) Torsional strength requirements apply only to austenitic steel screws and studs with nominal thread diameters M5 and smaller.

Coating Specifications

Renowned Brands

Bolting Components Marking

Product Shall be Marked with our manufacturing trade mark Adfast Component LTD along with the designated Grade.
Grade and manufacturer’s identification symbols shall be applied to one end of studs and to the heads of bolts and screws of all sizes. (If the available area is inadequate, the grade symbol may be marked on one end and the manufacturer’s identification symbol marked on the other end.) For bolts and screws smaller than 1⁄4 in. [6 mm] in diameter and studs smaller than 3⁄8 in. [10 mm] in diameter and for 1⁄4 in. [6 mm] in diameter studs requiring more than a total of three symbols, the marking shall be a matter of agreement between the purchaser and the manufacturer.

Property Class	Alloy Mechanical Property Marking
ASTM F738M A1-50	F738A
ASTM F738M A2-50	F738B
ASTM F738M A4-50	F738C
ASTM F738M A1-70	F738D
ASTM F738M A2-70	F738E
ASTM F738M A4-70	F738F
ASTM F738M A1-80	F738G
ASTM F738M A2-80	F738H
ASTM F738M A4-80	F738J
ASTM F738M F1-45	F738K
ASTM F738M F1-60	F738L
ASTM F738M C1-50	F738M
ASTM F738M C4-50	F738N
ASTM F738M C1-70	F738P
ASTM F738M C4-70	F738R
ASTM F738M C1-110	F738S
ASTM F738M C4-110	F738T
ASTM F738M C3-80	F738U
ASTM F738M C3-120	F738V
ASTM F738M P1-90	F738W
ASTM F738M P1-90	F738W

Dimensional Standards

ASME Bolt Dimensional Standards

B18.31.2 Imperial Continious Thread, Double End Reduced & Full Body Studs
B18.31.1M Metric Continious Thread, Double End Reduced & Full Body Studs
B16.5 Imperial Full Thread Stud Bolts
B16.5 Metric Full Thread Stud Bolts
B18.2.1 Imperial Square and Hex Bolts and Screws
B18.2.3.1M Metric Hex Cap Screws
B18.2.3.3M Metric Heavy Hex Screws
B18.2.3.5M Metric Hex Bolts
B18.3 Imperial Hexagon Socket and Spline Socket Screws
B18.3.1M Metric Socket Head Cap Screws
B18.6.7M Metric Machine Screws

Certification

Testing Standards

E18 Test Methods for Rockwell Hardness of Metallic Materials
E21 Test Methods for Elevated Temperature Tension Tests of Metallic Materials
E112 Test Methods for Determining Average Grain Size
E139 Test Methods for Conducting Creep, Creep-Rupture,and Stress-Rupture Tests of Metallic Materials
E150 Recommended Practice for Conducting Creep and Creep-Rupture Tension Tests of Metallic Materials Under Conditions of Rapid Heating and Short Times
E151 Recommended Practice for Tension Tests of Metallic Materials at Elevated Temperatures with Rapid Heating and Conventional or Rapid Strain Rates
E292 Test Methods for Conducting Time-for-Rupture Notch Tension Tests of Materials
E328 Test Methods for Stress Relaxation for Materials and Structures
E566 Practice for Electromagnetic (Eddy Current) Sorting of Ferrous Metals
E709 Guide for Magnetic Particle Testing
F606/F606M Test Methods for Determining the Mechanical Properties of Externally and Internally Threaded Fasteners, Washers, Direct Tension Indicators, and Rivets
F1940 Test Method for Process Control Verification to Prevent Hydrogen Embrittlement in Plated or Coated Fasteners
A962/A962M Specification for Common Requirements for Bolting Intended for Use at Any Temperature from Cryogenic to the Creep Range
A788/A788M for Steel Forgings, General Requirements

Threading Specs

Supplementary Requirements

S1	Additional Tests
S2	Alloy Control
S3	Permeability
S4	Passivation
S5	Shipment Lot Testing
S6	Heat Control

Product

Precision Components

Contract Manufacturing

Fastener

Resources

materials

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