Material number K02600: A36
K02600 is the Unified Numbering System designation for A36, carbon structural steel specified in ASTM A36.
What K02600 means
UNS numbers (ASTM E527 / SAE J1086) use a letter for the alloy family and five digits: G = AISI/SAE carbon and alloy steels (G41400 = 4140), S = stainless and heat-resisting steels (S30400 = 304), K = miscellaneous steels (K02600 = A36), T = tool steels, N = nickel alloys. The UNS number identifies a composition, not a product form or property level, so K02600 appears in several ASTM specifications (plate, bar, pipe) with different mechanical requirements.
A36 at a glance
ASTM A36 is the default structural carbon steel of North America: 250 MPa (36 ksi) minimum yield and 400–550 MPa (58–80 ksi) tensile for plate, shapes and bar, UNS K02600. Introduced in 1960 to replace A7, it defines what American engineers mean by 'mild steel' — cheap, ductile (20 % elongation in 200 mm), easily welded, bent and machined, and available from every service center as plate, angle, channel, flat and round. Chemistry is deliberately loose (carbon up to 0.25–0.29 % depending on thickness, no carbon-equivalent limit) because the specification guarantees mechanical properties rather than composition.
Since the late 1990s W-shapes (wide-flange beams) are almost exclusively rolled to A992 (345 MPa), and A572 Grade 50 has taken over much of the plate market where weight matters, so A36 today lives in plate up to 25 mm, angles, channels, bars, base plates, stiffeners and general fabrication. Bridge work uses A709 Grade 36, which adds Charpy zones; pressure vessels use A516, not A36.
The European counterpart is S235JR (weaker) or S275JR (stronger); JIS SS400, GB Q235B, GOST St3sp and IS 2062 E250 are the near or identical matches listed below. Note that A36 is not a bar grade like 1018: it specifies strength, 1018 specifies chemistry.
Full data sheet for A36 → · Equivalent grades →