904L Stainless Steel

904L stainless steel is a high-alloy austenitic steel composed primarily of iron, nickel, chromium, and molybdenum, with additions of manganese and copper.

This grade contains 19–23% chromium and 23–28% nickel—significantly higher than standard grades such as 304 and 316—giving it superior corrosion resistance in aggressive environments.

The “L” in its name denotes a low carbon content, which enhances weldability and reduces the risk of intergranular corrosion after welding.

A key feature of 904L is its 1–2% copper content, which provides excellent resistance to reducing acids like sulfuric acid. Combined with 4–5% molybdenum, the alloy also offers enhanced resistance to pitting and crevice corrosion, making it ideal for demanding applications in chemical processing, marine, and pollution control industries.

904L Stainless Steel Chemical Analysis

Weight Percentage

النيكل	23.0 min. to 28.0 max.
السيليكون	1.00
الكروم	19.0 min. To 23.0 max.
الفوسفور	0.045
Molybdenum	4.0 min. To 5.0 max.
الكبريت	0.035
Copper	1.0 min. To 2.0 max.
Iron	Balance
المنغنيز	2.00

(Room Temperature)

الموصلية الحرارية	11.5	W.m -1.°K-1
التمدد الحراري	15.8	μm/μm/°C
Specific Heat (0-100°C)	450	J.kg-1.°K-1
كثافة	7.95	g/cm3
المقاومة الكهربائية	9.52	μohm/cm
معامل المرونة	190	GPa

حِدّة	مُلَدَّن
Tensile Rm	490	MPa (min)
Tensile Rm	71	ksi (min)
Elongation (2” or 4D gl)	35	% (min)
R.p. 0.2% Yield	220	MPa (min)
R.p. 0.2% Yield	32	ksi (min)