Performance Characteristics of a Low Nickel-Molybdenum Pre-Alloy Steel Powder Compared to Conventional Alloy Powders

Ad-mixed nickel-molybdenum alloy powders currently present difficulties under conventional production conditions in that blending techniques may not produce material which are homogenous throughout.¹ This problem can be solved through the water atomization of a low alloy (nickel-molybdenum) molten steel.^2,3 In the production process of a water atomized molten steel, alloying elements such as nickel and molybdenum will become compounded during the steel melting stage, thus allowing for several improvements in physical properties when compared to an ad-mixed material. Most importantly, the homogeneous microstructures will allow for better sintered properties and performance characteristics. In this report, a low alloy nickel-molybdenum pre-alloy steel powder and its properties will be compared to conventional ad-mixed blends currently available.

This investigation compares green and sintered properties along with strength levels of pre-alloy powders and ad-mixed powders with increasing levels of nickel blended into the powder. The pre-alloy powders under investigation exhibit a compressibility and strength level which would be suited for certain part applications in the “as sintered” state. Additionally, conventional hardening and sinter hardening techniques could be utilized to further improve the performance of these powders.⁴