Mechanical Properties And Their Determination
Certainly, the mainly commonly performed test on engineering materials is the test of static tension. From such test many mechanical properties of material are estimated and understanding concerning to its behaviour is developed.
On the outset the distinction between dynamic and static load should be understood carefully. A "static load" is the one that changes extremely slowly along with respect to time throughout its application. Once applied, the static load keeps unchanged.
Very ordinary static tests that are presented for evaluation of mechanical properties are axial tension, torsional loading or flexural loading, compression loading. Axial load is applied beside the axis of specimen. Flexural loading is achieved via application of load perpendicular to the axis whilst torsional loading result from eccentric transverse forces that do not reason bending or change in length. Direct shearing test is performed also sometimes but is not a extremely popular test. In each this the load is gradually increased from zero till failure happens; rate of loading being such as definition of static load is not violated. Hardness is an extremely significant mechanical property that is determined also under static load via indentation. Tensile and Hardness strength are related. Fatigue is behavior of material beneath load or stress which remains changing along with time and failure depends on stress level and number of stress reversal. Creep is till now behavior under statically applied load over an extended period of time. Temperature plays a significant role in deciding such behavior.