主要成分 钢中碳含量一般按中下限控制为宜。钢中硅含量超过0.10%,随硅含量增加,钢的抗拉强度、硬度有所提高,但延伸率低,断面收缩率下降更,不利于冷变形。钢中锰含量适中,可改善钢中硫的存在形态和分布,有利于提高钢的冷成型性。 主要冷镦钢的牌号和成分见表1。 表1 各种冷镦钢的化学成分/% 生产厂 牌号 C Si Mn P S Als 马钢SWRCH18A 0.15~1.20 ≤0.10 0.09~0.60 ≤0.030 ≤0.035 ≥0.02 1018 0.15~1.20 ≤0.10 0.09~0.60 ≤0.040 ≤0.050 - ZL10A 0.70~0.12 ≤0.10 0.30~0.60 ≤0.035 ≤0.035 ≥0.02 ZL18A 0.15~0.20 ≤0.10 0.09~0.60 ≤0.035 ≤0.035 0.015~0.060 湘钢XSWRCH10K 0.06~0.12 0.05~0.20 0.25~0.05 ≤0.030 ≤0.030 - SWRCH35KC 0.32~0.37 0.12~0.20 0.45~0.60 ≤0.030 ≤0.035 - 宝钢SWRCH35K 0.32~0.38 0.10`0.35 0.60~0.90 ≤0.030 ≤0.035 - 天钢SWRCH18A、SWRCH22A 0.15~0.20 0.18~0.23 ≤0.10 ≤0.10 0.60~0.90 0.70~0.10 ≤0.030 ≤0.030 ≤0.035 ≤0.035 ≥0.02 ≥0.02 包钢ML35 ML42CrMo 0.32~0.40 0.38~0.45 ≤0.20 ≤0.30 0.30~0.60 0.50~0.80 ≤0.035 ≤0.035 Cr0.90~1.20 ≤0.035 ≤0.035 Mo0.15~0.25 - 0.02~0.05 Ni≤0.20 莱钢ML35 0.32~0.40 ≤0.20 0.30~0.60 ≤0.035 ≤0.035 Cr、Ni、Cu≤0.20 石钢ML35、 ML40、 ML45 0.32~0.40 0.37~0.45 0.42~0.50 ≤0.20 ≤0.20 ≤0.20 0.30~0.60 0.30~0.60 0.30~0.60 ≤0.035 ≤0.035 ≤0.035 ≤0.035 ≤0.035 ≤0.035 Cr、Ni、Cu≤0.25 Cr、Ni、Cu≤0.25 Cr、Ni、Cu≤0.25 杭钢CH35ACR 0.35~0.39 ≤0.10 0.09~0.60 ≤0.030 ≤0.030 Cr0.20~0 太钢ML07A ≤0.0.9 ≤0.10 0.30~0.60 ≤0.035 ≤0.035 - ML20MnTiB 0.17~0.24 ≤0.30 1.30~1.60 ≤0.035 ≤0.035 B0.0005~0.003 Ti0.04~0.10