Effect of the Porous Character on Ultimate Tensile Strength of Sintered Iron Compacts.

Sintering of sponge iron powder compacts at 930, 1000, and 1100 degree C for the period of 15 min to 16 hrs was found to cause considerable changes of their porosity characteristics and ultimate tensile strength. The changes are both numerical and dimensional, and the share of closed pores is increased. It is shown that the properties of the compacts are not sufficiently characterized by total porosity; they depend more on the features, geometry, distribution, and number of pores and, in particular, the share of closed pores.