Ihe ndị a na-akpụ akpụ bụ tumadi carbon steel na alloy steel, aluminom, magnesium, ọla kọpa, titanium na alloys sochiri ya. Ọnọdụ mbụ nke ihe ahụ bụ mmanya, ingot, ntụ ntụ na mmiri mmiri. Oke nke mpaghara obe nke igwe tupu na mgbe nrụrụ ka a na-akpọ...
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