Effect of Plastic Deformation of the Initial Components and Particle Size Reduction on the Structure and Properties of the PN85YU15-Ni Composite Material Produced by Spark Plasma Sintering

Abstract

Structure and mechanical properties of the PN85YU15 - Ni composite materials obtained by spark plasma sintering were investigated. Two types of powder mixtures, namely, nickel mixed with coarse-grained nickel aluminide and nickel mixed with fine-grained nickel aluminide were used to obtain the composites. Nickel aluminide and nickel powders were taken in the ratio 7:3 respectively. The effect of the initial nickel aluminide particle sizes and plastic deformation due to the ball milling on the structure and mechanical properties of materials sintered at 1100 °C and pressure of 40 MPa was determined. Plastic deformation and refining the initial intermetallic powder particle sizes leads to increasing the sintered material relative density to 95%. The tensile strength of the PN85YU15-Ni composite material obtained by sintering of the milled PN85YU15 powder and nickel in the ratio 7:3 was 1060 MPa. This value is almost twice as high as the tensile strength of the composite containing a no significant plastic deformed coarse-grained intermetallic compound powder (590 MPa), and three times higher than the tensile strength of the sintered nickel aluminide powder (380 MPa).