STATISTICAL-ANALYSIS OF SHRINKAGE VARIATION FOR POWDER INJECTION-MOLDING

A 2(4) factorial design was conducted to establish the effects of powd er injection molding (PIM) parameters on the shrinkage properties of t he widely used Fe-Ni powder system. Four process parameters were analy zed simultaneously: (i) the debinding method, i.e., solvent condensati on versus vacuum; (ii) the sintering heating rate; (iii) the sintering hold temperature; and (iv) the sintering hold time. Dimensional measu rements of the length, width and thickness of green and sintered recta ngular tensile specimens were made. An analysis of variance, together with the F-test, were used to determine the statistical significance o f each of the parameters on the length, width and thickness shrinkages .