短语词组短语high boron alloy steel 高硼合金钢boron intensified steel 硼强化钢boron n steel 硼钢boron bearing steel 含硼钢boron containing steel 含硼钢high boron cast steel 高硼铸钢boron n intensified steel 硼强化钢High Strength Boron Steel 高强度硼钢 返回 boron steel