题目碳钢按含碳量分类，中碳钢的含碳量范围是()。A. CB. C=0.3%~0.55%C. C>0.6%D. C=0.25%~0.6%碳钢按含碳量分类，中碳钢的含碳量范围是()。A. C<0.25%B. C=0.3%~0.55%C. C>0.6%D. C=0.25%~0.6%题目解答答案D. C=0.25%~0.6%