. Proceedings of the annual convention . i it should have a Brinellhardness of 218, and to meet the tensile strength specification of 100,000 psi it shouldhave a Brinell hardness of 193; these are the intersections of the lines through theplotted points with the 70,000 psi and 100,000 psi stress lines. Future Work Tests are in progress on 12 joints using 132 K44, headfrce, 36-in, 6-hole, long-toebars. Tests are planned on 132 RE bars with both ground and pressed easements; bothoil-quenched bars and oil-quenched and tempered bars will be included in the tests. Summary 1. Three tests of 132 RE h
. Proceedings of the annual convention . i it should have a Brinellhardness of 218, and to meet the tensile strength specification of 100,000 psi it shouldhave a Brinell hardness of 193; these are the intersections of the lines through theplotted points with the 70,000 psi and 100,000 psi stress lines. Future Work Tests are in progress on 12 joints using 132 K44, headfrce, 36-in, 6-hole, long-toebars. Tests are planned on 132 RE bars with both ground and pressed easements; bothoil-quenched bars and oil-quenched and tempered bars will be included in the tests. Summary 1. Three tests of 132 RE headfree bars specially oil quenched from 1550 deg F andtempered 1 hr at 800 deg F averaged 573,100 cycles. All of the failures started on thetop bar surface at a rail end. 2. Three tests of 132 RE headfree bars specially water quenched from 1550 deg Fand tempered 1 hr at 1000 deg F averaged 365,300 cycles. Four bars failed, 2 fromthe top and 2 from the base. Physical properties of these bars were all above AREAspecifications. i:.-o Rail. I3C -ic ;: 6-: -: s: ?: ::>: : : zz: :?: i^ Z50 260 BRiNELw HARDNESS ON TENSILE SPECIMENFiG S ^H^S Ci^ -J^r^E^ ES VS 5=; NELL OF FAILED JOINT BARS Rail 1237 3. Twelve tests of 132 RE headfrce bars specially oil quenched below the criticaltemperature at 1350 deg F averaged 71,400 cycles. Twenty bars failed, all from the topsurface at rail ends. Physical properties of these bars were only slightly above thephysical properties of non-heat-treated bars. 4. Ten tests of reheat-treated 112 headfree bars with large ground areas on thetop fi-shing surface (where cracks had been removed by grinding) averaged 852,660cycles; apparently the ground areas did not materially shorten the bar life. 5. Tensile tests on 85 specimens from failed bars from service revealed that 21percent passed the yield point .specification of 70,000 psi and 49 percent passed thetensile strength specification of 100,000 6. Micrographs on specimens from failed bars, bo
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