A.鉻、鎳、銅含量應(yīng)各不大于0.2% B.鉻、鎳、銅含量應(yīng)各不大于0.3% C.碳、鎳、銅含量應(yīng)各不大于0.3% D.碳、鎳、銅含量應(yīng)各不大于0.2%
A.±50mm B.0—+50mm C.0—-50mm D.±25mm
A.±0.2mm B.±0.3mm C.±0.4mm D.±0.5mm