单项选择题
A.90% B.80% C.85%
A.正火 B.调质 C.稳定化处理
A.Q235和18MnMoNBR B.20R和8MnMoNBR; C.18MnMoNBR和0Cr19Ni9 D.0Cr19Ni和18MnMoNBR