Abstract
Another serious problem in resistance welding has been the surface condition of the material being welded. The degree of cleaning needed to permit making satisfactory welds was not known. The effect of surface condition on eleotrode life was only partly known. It was generally believed that a commercial pickle was sufficient for all types of spot welding but that scaly steel could not be practicably welded unless the mill scale was first removed.; The early work on the spot welding of the heavier gauges of steel and the heat treatment of these welds was sponsored by the Office of Scientific Research and Development. The investigations on spot welding the thinner gauges of hardenable steels was supported first by the Office of Production Research and Development and later by the Welding Research Council. Both the Ingalls Iron Works and Bethlehem Steel Company supported the investigations on welding sealy steel. The studies in projection welding and the current work on welding the heavier gauges of steel are projects sponsored by the Welding Research Council.; Experimental results had also been obtained which questioned the validity of many of the arguments given in support of pulsation welding for the thicker gauges of steel. It was felt that the investigations should be continued in order to learn more definitely the proper teohnique for welding these materials and the reasons behind their different behavior. In addition, it was believed that additional data was needed on these processes in order to permit a wider use in industry.; Projection welding, which is closely akin to spot welding, has also been widely used industrially but this process, to an even greater extent than spot welding, has lacked a systematic investigation of the variables involved. The belief was wide spread that a study of the fundamentals of projection welding would provide a better understanding of the process and the effect of each variable, leading to a better selection of welding conditions by the industry in general.; Considerable initial work had been done at R.P.I. on these two problems. Spot welding of some hardenable steels had been done by using a tempering process which was carried out directly in the welding machine.; Fabrication of ferrous materials by means of resistance welding processes has been practiced for many years. However, much of this fabrication has been done using welding conditions which have had a rather inadequate basis for their selection. Consequently the results obtained were often erratic and not always dependable. Furthermore, the processes were limited in their extent. For example, spot welding was mainly restricted to sheet thicknesses below 1/4· and only non-hardenable, low carbon steel was satisfactorily welded. Some welding had been done on plate above 1/41 but the welding schedules were almost entirely based on pUlsation welding, the value of which was in question.; The different programs on spot welding and projection welding steel, as described in this report, were undertaken in an attempt to supply the answer to some of these questions. The report is presented in several sections, each the result of one or more different investigations. Since much of the testing eqUipment and technique was common to all of the projects, a general section on testing methods has been placed in an appendix.;
Description
June 1948; School of Engineering
Department
Dept. of Metallurgical Engineering;
Publisher
Rensselaer Polytechnic Institute, Troy, NY
Relationships
Rensselaer Theses and Dissertations Online Collection;
Access
Restricted to current Rensselaer faculty, staff and students. Access inquiries may be directed to the Rensselaer Libraries.;
