ASTM A554-08a - 1.10.2008
 
1. Scope

1.1 This specification covers welded stainless steel tubing for mechanical applications where appearance, mechanical properties, or corrosion resistance is needed. The grades covered are listed in Table 1.

1.2 This specification covers as-welded or cold-reduced mechanical tubing in sizes to 16 in. (406.4 mm) outside dimension, and in wall thicknesses 0.020 in. (0.51 mm) and over.

1.3 Tubes shall be furnished in one of the following shapes as specified by the purchaser: round, square, rectangular, or special.

1.4 Supplementary requirements of an optional nature are provided and when desired shall be so stated in the order.

1.5 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.

TABLE 1 Chemical Requirements

Grade
Composition, %
Carbon,
max
Manga-
nese,
max
Phos-
phorus,
max
Sulfur,
max
Silicon,
max
Nickel
Chromium
Molybdenum
Titanium
Columbium + Tantalum

Austenitic

MT-301

0.15

2.00

0.040

0.030

1.00

6.08.0

16.018.0

...

...

...

MT-302

0.15

2.00

0.040

0.030

1.00

8.010.0

17.019.0

...

...

...

MT-304

0.08

2.00

0.040

0.030

1.00

8.011.0

18.020.0

...

...

...

MT-304L

0.035A

2.00

0.040

0.030

1.00

8.013.0

18.020.0

...

...

...

MT-305

0.12

2.00

0.040

0.030

1.00

10.013.0

17.019.0

...

...

...

MT-309S

0.08

2.00

0.040

0.030

1.00

12.015.0

22.024.0

...

...

. . .

MT-309S-Cb

0.08

2.00

0.040

0.030

1.00

12.015.0

22.024.0

...

...

B

MT-310S

0.08

2.00

0.040

0.030

1.00

19.022.0

24.026.0

...

...

...

MT-316

0.08

2.00

0.040

0.030

1.00

10.014.0

16.018.0

2.03.0

...

...

MT-316L

0.035A

2.00

0.040

0.030

1.00

10.015.0

16.018.0

2.03.0

...

...

MT-317

0.08

2.00

0.040

0.030

1.00

11.014.0

18.020.0

3.04.0

...

...

MT-321

0.08

2.00

0.040

0.030

1.00

9.013.0

17.020.0

...

C

...

MT-330

0.15

2.00

0.040

0.030

1.00

33.036.0

14.016.0

...

...

...

MT-347

0.08

2.00

0.040

0.030

1.00

9.013.0

17.020.0

...

...

B

Ferritic

MT-429

0.12

1.00

0.040

0.030

1.00

0.50 max

14.016.0

...

...

...

MT-430

0.12

1.00

0.040

0.030

1.00

0.50 max

16.018.0

...

...

...

MT-430-Ti

0.10

1.00

0.040

0.030

1.00

0.075 max

16.019.5

...

5 × C min,

...

0.75 max

A For small diameter or thin walls, or both, where many drawing passes are required, a carbon content of 0.040 % max is necessary in grades MT-304L and MT-316L. Small outside diameter tubes are defined as those less than 0.500 in. (12.7 mm) in outside diameter and light wall tubes as those less than 0.049 in. (1.24 mm) in average wall thickness.

B The columbium plus tantalum content shall be not less than ten times the carbon content and not more than 1.00 %.

C The titanium content shall be not less than five times the carbon content and not more than 0.60 %.

 
2. Referenced Documents

SAE J 1086

Numbering Metals and Alloys

MIL-STD-163

Steel Mill Products Preparation for Shipment and Storage

Fed. Std. No. 123

Marking for Shipments (Civil Agencies)

MIL-STD-129

Marking for Shipment and Storage Available from Standardization Documents Order Desk, Bldg. 4 Section D, 700 Robbins Ave., Philadelphia, PA 191115094, Attn: NPODS.

E527-23

Standard Practice for Numbering Metals and Alloys in the Unified Numbering System (UNS)

A941-26a

Standard Terminology Relating to Steel, Stainless Steel, Related Alloys, and Ferroalloys (Includes all amendments and changes 4/15/2026).

A790/A790M-24

Standard Specification for Seamless and Welded Ferritic/Austenitic Stainless Steel Pipe

A751-25

Standard Test Methods and Practices for Chemical Analysis of Steel Products

A370-26

Standard Test Methods and Definitions for Mechanical Testing of Steel Products