SEVEN basic copper-tin-lead bearing-bronzes having high copper contents were studied by the application of various mechanical tests, such as Brinell hardness, resistance to impact, resistance to repeated pounding and resistance to wear. The effects of various additions were investigated by preparing test bearings of the same base alloys with additions of zinc, phosphorus, nickel and antimony, taken singly, and applying the same tests to these.
The preparation of the test castings and the methods of testing are described in detail. The chemical analyses are given for the 40 different alloys tested; and the results of the various tests on each group of alloys are reported and discussed in detail, with the observations charted and tabulated for convenient reference.
A tabulation of the specifications of 54 different bearing bronzes now in use is included in the paper.
Dr. Dowdell presented and discussed∗ the paper for the authors. The discussion emphasized the necessity of complete film lubrication and mentioned porous synthetic bearing alloys as a means of securing this. Contributed discussion called attention to improvements and economies that could be made in specifying and purchasing bearing bronzes by consultation with bearing manufacturers.