Patent ID: 9663407
Date: 2017-05-30
CPC Classifications: C04B,F16C

Claim:
1. A silicon nitride wear resistant member comprising a silicon nitride sintered compact containing β-Si 3 N 4 crystal grains as a main component, 2 to 4% by mass of a rare earth element in terms of oxide, 2 to 6% by mass of Al in terms of oxide, and 0.1 to 5% by mass of Hf in terms of oxide, wherein, the silicon nitride sintered compact has rare earth-Hf—O compound crystals, wherein, in an arbitrary section, an area ratio of the rare earth-Hf—O compound crystals in a grain boundary phase per unit area of 30 μm×30 μm is 5 to 50%, wherein a variation of five area ratios, which do not overlap each other, of the rare earth-Hf—O compound crystals between the unit areas is 10% or less, and wherein, when the silicon nitride sintered compact is subjected to XRD analysis, an intensity I1 of a peak at 30.0±0.5° based on the rare earth-Hf—O compound crystals, an intensity I2 of a peak at 27.1±0.5° and an intensity I3 of a peak at 33.7±0.5° based on the β=Si