英文關鍵字
abstract
acetylene
aluminiu
aluminium
aluminum
background
bar
billet
bright
bullion
business
commerce
construction
equipment
factory
heavy
industrial
industry
ingot
ingots
iron
labor
labour
lead
lump
manufacturing
material
melt
metal
metallic
plate
plates
platinum
pot
production
profile
raw
rough
silver
smelt
smelting
stack
stacked
steel
stock
substance
welder
welding
zinc