Showing papers on "Weldability published in 1971"
01 Jan 1971
TL;DR: Inconel 718 has very good weldability as discussed by the authors, but the difficulty of obtaining good penetration with the root pass is encountered in most nickel-base alloys and is due to the poor fluidity of the molten metal.
Abstract: Penetration In general, Inconel 718 has very good weldability. Welding tests were made using gas metal-arc (GMA) and gas tungsten arc (GTA) processes and satisfactory results were obtained. Welds were also made in the unaged and aged conditions and no major difficulties arose. The one problem always encountered was the difficulty of obtaining good penetration with the root pass. This is encountered in most nickel-base alloys and is due to the poor fluidity of the molten metal. It was therefore decided to study this aspect more closely and to try to
31 citations
Patent•
27 May 1971
TL;DR: In this article, high melting material to be welding is wetted with Pt, pref. alcoholic H2PtCl6 soln. and then heat-treated in a reducing atm, such as H2, whereby an adherent pure Pt layer about 1 mu m thick is deposited on the material.
Abstract: High melting material to be welding is wetted with Pt, pref. alcoholic H2PtCl6 soln. and then heat-treated in a reducing atm., such as H2, whereby an adherent pure Pt layer about 1 mu m thick is deposited on the material. Process is useful for increasing weldability of electrode parts consisting of Mo and W, used in Hg high pressure- or halogen lamps containing assemblies consisting of Mo foil, Mo wires and Mo or W vacuum-sealed electrode rods.
3 citations
TL;DR: In this paper, the effect of Co-60 on the fundamental characteristics, weldability and adhesiveness of polyethylene was investigated, and it was concluded that the increase of cross linkings due to irradiation makes weldability lower and carbonyl groups whose existences have been confirmed by infrared spectra analysis imdrove adhesion.
Abstract: This paper purports to inrestigate the effect of irradiation by Co-60 on the fundamental characteristics, weldability and adhesiveness of polyethylene.High pressure polyethylene films, 0.07 mm in thickness, were used in this experiment and exposed to various irradiation doses up to 5×107r under various ambient conditions. Measurements of degree of crystallization, resolution rate in xylene, wettability and others were made. These materials were welded with heated tool or bonded by various adhesives and then experiments on boniing strength were performed.The results are summarized as follows:Decay of crystal and change of degree of crystallization about irradiated polyethylene were not recognized within the ilmits of this experiment. It can be concluded that the increase of cross linkings due to irradiation makes weldability lower and carbonyl groups whose existences have been confirmed by infrared spectra analysis imdrove adhesiveness.
2 citations
TL;DR: In this article, a new machine has been developed to test the fatigue strength of spot welds in high tensile steels and to check the reliability of the welded joint of these steels in SHIN KANSEN electric railcars.
Abstract: This paper, following the previous report that dealt with the method of selecting the heat-treatment conditions of spot welds in anti-corrosive high tensile steels, gives details of the weldability assessment of these steels.The ductility ratio of these steels is about 50% as welded. But it can be improved by tempering to about 70%. Under combinations of these steels and low carbon steels, it can be improved to about 80% by tempering.The objective of this study was to check the reliability of the welded joint of these steels in SHIN KANSEN electric railcars structures. Therefore, a strict test had to be carried out on the joint.A new machine has been developed to test the fatigue strength of spot welds in these steels. The testing data show that the efiect of heat-treatment on the improvement of ductility of spot welds and the relationships between the fatigue strength of spot welds and the welding conditions can be easily analyzed.Meanwhile, the crack initiating mechanism of spot welds in fatigue failure has been clarified.The experimental work has shown that a clean scale-free surface and high electrode force are essential for the uniform tempering of spot welds.
2 citations
Patent•
16 Apr 1971
TL;DR: Ferrous material has C below 020 wt% and Nb 0025-0065 wt%, rest Fe, and has an appropriate shape for hot reduction as discussed by the authors, it is heated to max 1175 degrees C and reduced to plate thickness at a temp above the A3 critical point.
Abstract: Ferrous material has C below 020 wt% and Nb 0025-0065 wt%, rest Fe, and has an appropriate shape for hot reduction It is heated to max 1175 degrees C and reduced to plate thickness at a temp above the A3 critical point Pref, it contains 090-150 wt% Mn, and is a killed or semi-killed steel
1 citations
01 Jan 1971
1 citations
TL;DR: In this paper, the authors explained the effect of surface cleanliness on the solid phase weldability of metals, and clarified the influences of welding factors such as temperature, pressure and duration on the mechanical strength of the welded joint.
Abstract: The purposes of this study are to explain the effect of surface cleanliness on the solid phase weldability of metals, and to clarify the influences of welding factors such as temperature, pressure and duration on the mechanical strength of the welded joint In the experiment, the surfaces to be welded are polished by a wire brush made of stainless steel in the environment in the ranges 760-2×10-6 torr and then these metals are welded without melting under various welding conditions. The quality of the welded joint is evaluated by the tensile shear test at room temperature and the following results are obtained.1. The wire-brushing in high vacuum is a very useful technique for the improvement of the weld quality, and that the surface cleanliness of metals to be welded is a principal factor for the solid phase welding in high vacuum.2. The quality of welded joint is affected by the surface treatment and welding atmospheric pressure or the exposure to the environment befor welding, and these influences become more and more remarkable with a decreasing welding temperature.3. The effects of the welding temperature and pressure on the mechanical strength of the solid phase weld made in high vacuum are noticeably greater than those of the welding duration.4. In the solid phase welding at the temperature of the order of 35 percent of the absolute melting temperature of metal to be welded, the weldability of the metal is mainly affected by the reaction between the metal to be welded and the residual gases in vacuum chamber. Therefore, the solid phase weldability of the metal such as silver and copper which has much weaker affinity for gaseous oxygen is better than that of the metal such as magnesium, aluminum and titanium which has much stronger affinity for gaseous oxygen.
1 citations
Patent•
29 Oct 1971
TL;DR: The (C+N) content of steel is limited which prevents the formation of carbide and nitride which causes brittleness during cooling after casting as discussed by the authors, and the steel has comparatively large strength as cast.
Abstract: Steel comprises 0.07% C, 0.1% (C+N), 0.1-1.0% Si, 0.2-4.0% Mn, 4.5-7.5% Ni, 16-22% Cr, 0.5-1.5% Mo and balance Fe. The (C+N) content is limited which prevents the formation of carbide and nitride which causes brittleness during cooling after casting. The steel has comparatively large strength as cast, good cavitation corrosion resistance and weldability.
1 citations