A variety of mechanical properties can be achieved for carbon and alloy steel castings by altering the composition and heat treatments of cast steels.
Foundries utilize specialized testing methods to check mechanical properties prior to product completion.
When it comes to cast steel testing, there are two types of testing used in industry: destructive and non-destructive testing.
Destructive testing requires the destruction of a test casting to visually determine the internal soundness of a part. This method only provides information on the condition of the piece tested, and does not ensure that other pieces will be sound.
Non-destructive testing is employed to verify the internal and external soundness of a casting without damaging the casting itself. Once the casting passes the tests, it can be used for its intended application.
Tensile properties
Tensile properties for steel castings are an indication of a casting's ability to withstand loads under slow loading conditions. Tensile properties are measured using a representative cast sample that is subject to controlled tensile loading—pulling forces exerted on either end of the tensile bar—until failure. Upon failure, tensile properties are examined.
Tensile Properties |
Properties |
Description |
Tensile Strength
Yield Strength
Elongation (%)
Reduction of area (%) |
Stress required to break a casting in tension, or under a stretching load.
Point at which a casting begins to yield or stretch and demonstrate plastic deformation while in tension.
Measure of ductility, or the ability of a casting to deform plastically.
Secondary measure of a casting’s ductility.
Demonstrates the difference between original cross-sectional area of the tensile bar, and area of smallest cross section after failure in tension. |
Bend properties
Bend properties identify a casting's ductility by using a rectangular representative sample bent around a pin to a specific angle. The resulting bent bar is observed to check for objectionable cracking.
Impact properties
Impact properties are a measure of toughness resulting from testing the energy required to break a standard notched sample. The more energy required to break the sample, the tougher the cast material.
Hardness
Hardness is a measure of a casting's resistance to penetration using indentation tests. It is a property that indicates wear and abrasion resistance of cast steels. Hardness testing can also provide an easy, routine method to test for indications of tensile strength in a production environment. A hardness scale test result will normally correlate closely with tensile strength properties.
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