抄録
Boronizing is one of the chemical methods to achieve case hardening of steels. The boronized layer has above 1400 Vickers hardness and a high resistance especially against wear. In the present study, the X-ray method was successfully applied to measure the residual stress distribution in a boronized steel. The X-ray elastic constants were determined separately for FeB and Fe2B phases of the boronized layer, and compared with the mechanically measured values. The results obtained are summarized as follows;
(1) The X-ray elastic constants determined were
S1=9.10×10-7(MPa-1), S2/2=2.93×10-6(MPa-1)
for FeB (212) phase, and
S1=4.95×10-7(MPa-1), S2/2=2.13×10-6(MPa-1)
for Fe2B (330) phase.
The Young's modulus of FeB and Fe2B phases were 494(GPa) and 611(GPa) which were higher than the mechanically determined values of 370(GPa) and 260(GPa), respectively.
(2) The residual stress distribution determined by X-rays indicated high compressive stress above 2000(MPa) in the boronized layer. The effect of the boronizing process on the residual stress distribution was examined.
