PRELIMINARY INVESTIGATION OF THE EFFECT OF SURFACE TREATMENT ON THE STRENGTH OF A TITANIUM CARBIDE - 30 PERCENT NICKEL BASE CERMET

摘要

The effect of various surface treatments on the room-temperature modulus of rupture and impact strength of a nickel-bonded titanium car-bide cermet were investigated. The average strengths for the treatments varied from about 200,000 to 80,000 pounds per square inch in modulus of rupture, and about 3.5 to 1 inch-pound in impact resistance. The strengths of lapped, grit-blasted, diamond-ground, or vapor-blasted specimens were not significantly different. The most serious losses of strength occurred after oxidation (at 1600℉ for 100 hr), surface roughening by acid attack, and severe grinding with a 60-grit silicon carbide abrasive wheel. The modulus-of-rupture strength of oxidized specimens was improved after grit blasting or regrinding with a diamond abrasive wheel. The magnitude of the changes in impact and modulus-of-rupture strengths for some surface treatments were quite different.