CARBON STEEL & CAST STEEL

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The header of the question is obvious

carbon steel = Iron carbon solid solution with no significant alloying elements except deliberate ones (like Mn, Si etc in controlled amount - max for deoxidation)

It can be plate (carbon steel plates), castings (carbon steel casting or cast carbon steel), forgings etc.

It can be further divided depending on c% - Low, medium, or High carbon steel, microstructure, etc.

Cast Steel are Steel (any type - Stainless, Alloy etc) castings.

Thus both the nouns are incomplete, even when we do not specify,

Usually we talk in terms of Cast carbon steel to ASTM A216, carbon Steel Forging to SAE1035 etc.

No cast steel has more temper.

Not sure what you mean by that.

milo

So, how about cast carbon steel?

Lets look at the terminology involved before we get to far out of line here.

Casting is a process. It is a process of producing a solid shape from a liquid material by controlling the geometry and cooling using a mold. Foundries cast steel into discrete items, using individual molds for each item.

Continuous casting is a process whereby liquid steel is continuously solidified into a long billet or bloom which can be subsequently rolled into final shape on a rolling mill.

This material, after rolling in the mill, is called wrought, as in hot wrought. Think of wrought as anachonistic word meaning "worked".

Hot wrought steel bars can be pulled through carbide dies to make cold finished or bright bars. They are said to be cold finished steel in North America, Bright Steel in UK and EU, in my experience.

Carbon steel describes a ferrous material having no minimum quantity specifed for any alloying elements oither than Manganese, (below 1.30 wt%; Carbon, Sulfur, and Phosphorous, as well as deoxidizers and grain refiners such as small amounts Silicon, aluminum, Columbioum(niobium) Vanadium.)

Carbon steel can be continuously cast , then hot wrought and cold worked.

It can also be forged into a forged shape to refine the grain structure and give it strength.

Carbon steel can also be cast into individual items such as a machinery part, in which it would be correctly described as a carbon steel casting.

FYI, CAsting has coarser grain structure, and lower mechanical properties. Hot rolling and forging improve the materials structure and strength; cold drawing similarly boosts tensile and yield strength while sliughtly decreasing DUctility as measured by % elongation and % red of area.

Temper is a word that describes the relief of stresses after an heat treatment where the steel is austenitized and quenched to form a martensitic structure. Tempering involves reheating the hardened steel to a temperature below its eutectoid temperature to slightly reduce its hardness and improve its toughness.

I have heard the word temper used by old timers in the tool steel business as a synonym for carbon content, but that wasa localized "tribal knowledge" kind of thing, as hardness does follow carbon content. Such communication is not compatible with todays ISO standards and the amount of litigation in the world.

Martensite is extremely brittle, and the application of a low temperature "tempering treatment" allows some of the residual stresses to be relieved , leaving the Quench and tempered steel much stronger and tougher.

It is my professional opinion that this martenistic transformation of steel is the original "Nanomaterial" produced by human ingenuity.

milo