【单选题】104 / 441直角角焊缝有效厚度取?A0.7hf0.7h_f0.7hf正确Bhfh_fhfC1.5hf1.5h_f1.5hfD0.5hf0.5h_f0.5hf参考答案A参考解析0.7hf。