The strength of a drawn pearlite wire of a hypereutectoid steel was examined by tension and compression test. To make clear the reason why the drawn wire shows yield strength anisotropy, texture and residual stress were investigated by neutron diffraction. The influence of annealing on these results was also examined. The followings are main results obtained. (1) Specimens as-drawn or aged at 423K after the drawing show large strength difference between tension and compression. The strength anisotropy is confirmed by compression test for specimens prepared along directions of 0, 45 and 90 degrees with respect to the drawing direction. This anisotropy disappears when a specimen is annealed at an elevated temperature above 698K. (2) The texture in an as-patented specimen was weak. The <110> fiver texture was evolved by the drawing and it did not disappear by annealing at 698K. (3) The residual lattice plane strains were observed in the as-patented specimen. The strains are not relaxed by annealing at 423K but almost relaxed to a negligible level at 698K. (4) Because the specimen annealed at 698K with the <110> texture and little residual stress showed the isotropic yield strength, the residual stress in the ferrite matrix balanced with those in cementite is concluded to cause the strength anisotropy of as-patented wire. (5) The influence of selected (hkl) on the lattice plane strain is caused by heterogeneous deformation among blocks with different orientations accompanying block stress.
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