Powder metallurgy for the mixed powder and its production method, as well as iron-based powder made of sintered body with excellent cutting properties and its manufacturing method

摘要

PROBLEM TO BE SOLVED: To provide mixed powder with which a sintered body having both excellent machinability and drill cuttability can be obtained.;SOLUTION: The mixed powder for powder metallurgy is obtained by mixing iron-based powder, powder for an alloy, powder for improving cuttability and lubricant powder. The powder for improving cuttability includes powder capable of forming an SiO₂-MgO amorphous phase or an SiO₂-MgO-alkali metal oxide amorphous phase and an oxide phase including SiO₂ or magnesium oxide (MgO). Examples of the powder for improving cuttability includes enstatite powder, talcum powder, kaolin powder, mica powder, water-granulated slag powder, magnesium oxide (MgO) powder, and mixed powder of SiO₂ and MgO. Further, the powder for improving cuttability may be blended with metal boride powder and metal nitride powder serving as hard metal compound particles and MnS and CaF₂ serving as soft metal compound particles. The sintered body produced from the mixed powder has a base phase in which a soft metal compound phase having a hardness lower than the average hardness of the base phase and a hard metal compound phase having a hardness higher than the average hardness of the base phase are dispersed, thus having excellent cuttability including both excellent lathe cuttability and cuttability.;COPYRIGHT: (C)2012,JPO&INPIT