A.HRB B.HPB C.RRB D.LRB
A.低碳鋼可焊性好 B.合金元素會(huì)降低可焊性 C.硫?qū)附有圆焕?br /> D.磷對(duì)鋼材焊接有利
A.可節(jié)約鋼材 B.會(huì)降低塑性 C.可提屈服強(qiáng)度 D.伸長(zhǎng)率提高