44SMn28 · Free-cutting steel wire rod

44SMn28 · EN ISO 683-4-2018

Free-cutting steel semi-finished products, bars and wire rod; see delivery-state and dimensional conditions · Table 2 and notes a–c; Table 3; 1,6.3,7.1,7.3 · PDF page 1、5、7、10、13、14、15 · Mass fraction %

Based on the official EN ISO683-4:2018 text, consulted as DIN EN ISO683-4:2018-09; The European foreword confirms the adoption of ISO683-4:2016 without modification; 2018 is the EN adoption version year, while the adopted ISO version remains 2016. The scope includes semi-finished products, bar products, and wire rod of the free-cutting steels listed in Table 2; Bright bars shall refer separately to ISO683-18; standards for different products shall not be automatically conflated. Table 2 is for heat analysis; Verify Table 3 permissible product-analysis deviations separately only when required at ordering; deviations for the same heat must not exceed both the upper and lower limits in opposite ± directions. Grades containing Pb and grades without Pb shall be recorded separately; dashes shall not be filled as 0. The default low Si value for the non-heat-treated group shall be kept separate from the agreed Si 0.10–0.40% under special oxide guarantees; P shall be selected from a default maximum of 0.11%, an agreed range of 0.06–0.11%, or an agreed maximum of 0.05%; agreed conditions shall not be adopted automatically. Elements not listed shall not be intentionally added without the buyer's consent (except additions needed to finish steelmaking); Additions to improve machinability, such as Ca, Se, and Te, must be agreed upon and reported in the inspection documents; the complete carbon equivalent shall not be calculated based on missing items. Table 1: Untreated +U applies to semi-finished products, bar products, and wire rod; +QT delivery condition applies only to bar products listed in Table 1. Agreed properties for untreated products based on reference samples after heat treatment do not mean that wire rod has been quenched and tempered upon delivery. +U hardness in Tables 4–6 shall be kept separate from the tensile strength used for dispute arbitration; In case of dispute, determination shall be based on tensile strength; properties after quenching and tempering shall not be used to replace the untreated delivery condition. No values are listed for the first and last diameter intervals of +QT for 35SMn20/35SMnPb20 in Table 6; dashes shall not be filled as 0 or extrapolated from adjacent diameters; Parentheses for the first two hardness levels of the 44SMn28 group shall be retained as per the original text; the meaning of parentheses and the guarantee range shall be verified separately. Tensile specimens shall be according to Table 7 and ISO6892-1, with a proportional gauge length L0=5.65√S0; Sampling location, cross-section, inspection lot, and inspection document requirements shall be verified separately. According to 7.3, welding is generally not recommended for high S/P free-cutting steels; Suitability for cold heading or other cold forming must also be confirmed in conjunction with the actual material and agreement; material retrieval does not equal processing suitability or supply guarantee.

Original source: EN ISO 683-4:2018