An Initial Appraisal of the Contact Fatigue Strength of Electron Beam Melted Bearing Steel

Three test groups of 2.75 in. bore tapered roller bearings were manufactured from pilot heats of cold hearth electron beam remelted modified 4620 steel, a heat of standard consumable electrode vacuum remelted (CV) 4620 steel and from conventionally melted modified 4620 bearing steel. Bearing life tests were performed in a synthetic fluid and two mineral oils of different viscosity to determine the contact fatigue strength of the electron beam melted steel as compared to the CV steel and conventional steel. The electron beam and the consumable vacuum melted steel had equivalent contact fatigue strength in this initial appraisal. The CV steel had contact fatigue strength 4.5 to 9.8 times better than the conventional bearing steel.