A MECHANICAL ANALYSIS OF THE CONSTITUTIVE PARAMETERS IN THE SEMIVISCOSITY FLOW EQUATIONS UNDER THE SUPERPLASTIC TENSION CONDITIONS

Based on the review of the history of research on the constitutive par ameters m and k of the semiviscosity flow equations under the superpla stic tension conditions, the differential relation including m and K a s variables is built. By means of the curve which imitates the relatio n between strain-rate sensitive index m and strain-rate (epsilon) over dot, the analysis expression of m((epsilon) over dot), k((epsilon) ov er dot) and the relations of K vs. m is theoretically obtained. It has been proved that m is the parameter of strain-rate sensitivity and th e value of K is variable that can be determined with m. Therefore, a m echanical analysis theory on m and K is established. The theoretical c urves fit well the practical curves for three types of alloys with sup erplastic property. The multinomial expression of curves m((epsilon) o ver dot) and K((epsilon) over dot), which are accurately imitated for the above alloys, is given for the sake of quantitative calculation.