铜及铜合金焊接方法
normal welding of copper and copper alloy
铝合金焊接接头
welded joints in aluminium alloy
Al-alloy joint
welded joints in aluminum alloy
首饰用K金合金
Karat gold alloys for jewelry
硬质合金焊接式锥柄机用铰刀
carbide welded taper shank machine reamer
仿金铜合金
gold imitating copper alloy
高纯度铜锌合金颗粒
high pure copper and zinc alloy granule