80

Heat analysis, mass fractions wt%; Product-analysis tolerances are assessed separately under GB/T222 and are not included in this table. ; Table 1, note b: when required by the purchaser and stated in the contract, residual Cu may be ≤0.20%; Default tabulated limit ≤0.25%. ; 6.1.2: oxygen in 40SiMnVBE is ≤0.0015%; oxygen in other alloy spring steels is ≤0.0025%; This limit is not extended to carbon spring steels. ; Unspecified elements do not mean zero; Spring-steel composition does not establish suitability for every cold-headed component; the specific process requires a separate assessment.

The chemical composition currently shown is transcribed from the original GB/T 1222-2016; The original record cites GB /T 1222-2025; that original edition remains unavailable, and differences between editions have not been confirmed. Heat analysis, mass fractions wt%; Product-analysis tolerances are assessed separately under GB/T222 and are not included in this table. ; Table 1, note b: when required by the purchaser and stated in the contract, residual Cu may be ≤0.20%; Default tabulated limit ≤0.25%. ; 6.1.2: oxygen in 40SiMnVBE is ≤0.0015%; oxygen in other alloy spring steels is ≤0.0025%; This limit is not extended to carbon spring steels. ; Unspecified elements do not mean zero; Spring-steel composition does not establish suitability for every cold-headed component; the specific process requires a separate assessment.

Edition 1999, main-text Table 1, row 19, unified numerical designation U20802. This record uses the default quality-steel class; heat analysis, mass fraction %. Table 2: for quality steel, P and S are each ≤0.035%; for higher-quality class A, each is ≤0.030%; for special-quality class E, the requirements are P≤0.025% and S≤0.020%. Do not apply A/E limits to the default class. 6.1.1.2—3: scrap-based steelmaking may permit Cu≤0.30%; steel for hot pressure working requires Cu≤0.20%. This record retains the default Cu≤0.25% in Table 1; specific conditions require separate confirmation. 6.1.1.4: Mn/Cr/Ni/Cu for lead-patented steel wire 35—85 has a separate restriction and does not apply to this default structural-steel record. Mechanical properties in Table 3 and 6.4 depend on specimens, dimensions, heat treatment and order requirements. Existing reference properties are not upgraded to universal guarantees by this composition review.

Table 1 of GB/T699-2015 gives heat-analysis mass fractions wt%; Product-analysis tolerances are listed separately under GB/T222. ; Table 1, note a: Cu≤0.20% for steel intended for hot pressure working; other tabulated cases are ≤0.25%. ; 6.1.2: N≤0.008% applies to basic oxygen steelmaking; analysis may be omitted if the supplier guarantees compliance; Applicability depends on the steelmaking method. ; 6.1.3: for lead-bath-patented wire, Mn0.30–0.60% for 35–85 and Mn0.70–1.00% for 65Mn/70Mn, Cr≤0.10/Ni≤0.15/Cu≤0.20%; P/S follows the corresponding wire standard and must not exceed Table 1. This is a conditional exception, not a general range. ; Elements not specified in the table must not be intentionally added without purchaser consent.

A match in the materials database does not establish suitability for cold heading or guarantee finished-product strength. Confirmation must consider wire condition, deformation, heat treatment and tests on actual parts.