ML28B

Clause 6.1.1 of GB/T5953.1/.2:2009 follows the relevant standards identified in the contract; This is reference composition for the same designation under GB/T6478; the applicable standard must be confirmed by contract, and these values are not directly treated as mandatory composition under 5953. Historical data from an earlier edition. No edition is stated on the website; Displayed under this source edition; contract applicability is not established

Mass percent, heat analysis, GB/T28906-2025 Table 4. ; 7.1.5 residual Cr/Ni/Cu are each ≤0.20% and Sn≤0.06%; tabulated alloy Cr is not subject to the residual maximum; 7.1.7 product-analysis tolerances follow GB/T222 and must not be directly treated as heat-analysis limits. ; The standard scope for hot-rolled cold-heading wire rod does not replace confirmation of actual supply dimensions and the component manufacturing process; Mechanical properties require separate verification. ; When measuring acid-soluble aluminum, Als0.015–0.055% is used and is retained separately from total aluminum Alt0.020–0.060%; The Al element field must be interpreted with the selected measurement condition. ; Table 4 Note a: A Si lower limit below 0.10% may be negotiated and specified in the contract; do not fill in without agreement. ; Note b: When hardenability and mechanical properties meet requirements and upon mutual agreement, the lower limit of B may be relaxed to 0.0005%; Default 0.0008%. ; Note c: The Ti/N ratio may be agreed upon, but as no uniform value is provided in the original text, it shall not be automatically set or declared as satisfied. ; Note e: Cr may be added by agreement for the first 15 grades, with the addition amount to be confirmed by both parties.

GB/T6478-2001, Table 4, heat analysis wt%; 6.1.4 residual Cr/Ni/Cu are each ≤.20%; alloy Cr ranges are not subject to the residual maximum. ; 6.1.8 product-analysis tolerances require separate verification under GB/T222-1984, Table 2, and do not widen the default heat-analysis range. ; Actual 2001 edition; Composition from editions 2015 or 2025 is not substituted for this edition; specific dimensions and delivery mechanical properties require separate verification. ; Table 4 total aluminum Alt≥.020%; An acid-soluble aluminum determination satisfying Als≥.015% is also acceptable; Default B in this edition is .0005–.0035%.