BS in Materials Engineering
Materials Engineering Department
Three iron-based hardfacing alloys were fabricated to have a tungsten strengthened matrix with varying compositions of 10-15, 20, and 30 wt% tungsten/chrome boride content. The fourth sample was fabricated to have a molybdenum solid solution strengthened matrix with 10-15 wt% W/Cr Boride content. This project focuses on the compressive strength of iron-based hardfacing alloys. Preliminary compression tests with Scoperta iron-based hardfacing alloys showed a need for sample dimension reduction due to compressive loads that could not be met by a 50 kN maximum capacity mechanical testing system. The preliminary tests showed compressive strengths exceeding 2340 MPa. Samples of the current alloys were electro discharge machined (EDM) to cylinders with 3 mm diameters and 2.41 mm heights. Hardened 440C stainless steel platens were used to compress the samples in a compression testing setup using a 50 kN capacity mechanical testing system. The molybdenum solid solution strengthened hardfacing alloy with 10-15 wt% W/Cr Boride content showed an average compressive strength of 4346 MPa, while the tungsten strengthened matrix with the same 10-15 wt% W/Cr Boride content showed an average compressive strength of 4107 MPa. The 20 wt% W/Cr Boride content alloy showed a compressive strength of 3378 MPa, and the 30 wt% W/Cr Boride content alloy showed an average compressive strength of 2713 MPa. Each of the data sets was statistically significantly different with a 95% confidence interval.