ML35CRMOV

GB/T28906-2025 Table 3: Hot-rolled wire rod of quenching-and-tempering-type cold-heading steel; heat analysis, mass fraction %.. ; Note a: Aluminum may be added to improve cold-heading performance, with Alt≤0.060%; this option does not make addition mandatory by default.. ; Note b: Through negotiation between the supplier and the buyer, Si may be lower than 0.10%; In this case, aluminum must be added and Alt≥0.020%.. This record defaults to the Si range listed in the table; do not arbitrarily fill in when no specific low-silicon agreement range is given. ; Note c: For the first 11 grades in Table 3, Cr may be added by agreement to improve hardenability and mechanical properties; the addition amount must be confirmed by both parties; When no agreement is provided, residual Cr ≤ 0.20% according to 7.1.5. ; 7.1.5 Residual Cr, Ni, and Cu are each ≤ 0.20%, and residual Sn ≤ 0.06%; The residual Cr upper limit is not applicable when Cr has a listed alloy range in the table. ; 7.1.7 Unless otherwise specified in the table, the permissible deviation of the finished product chemical composition shall be according to GB/T222; heat analysis values shall not be substituted for finished product tolerances. ; The original text applies to 5–52mm hot-rolled wire rod for cold heading; specific product specifications, supply, and processing routes still need to be confirmed; Mechanical properties to be verified separately. ; Table 3 Note d: Can be used for heat-resistant fasteners, maximum service temperature 550℃, which is not equal to the design allowable stress in the unverified state..