Fatigue strength of laminated materials of dissimilar metals and alloys

Abstract

Various laminated bars and plates were made combining some steels and face centered cubic metals and alloys by adhesive-bonding, casting and hot rolling. The fatigue tests were performed on the notched bar and notched plate test specimens of these laminated materials, and effects of each surface material and joining method were compared. The experimental results obtained were as follows:
(a) Adhesive-bonded laminated bars with core mild steel and surface materials of stainless steel, copper, 60/40 brass and aluminum showed larger fatigue strength than that of solid mild steel bar. With 1mm in surface thickness, the laminated bar of stainless steel had the largest fatigue strength and that of aluminum the smallest of all the tested laminated bars, but with 0.5mm in surface thickness, there was little difference between the fatigue strength of those kind of surface materials.
(b) The fatigue strength of adhesive-bonded copper-80kg/mm² high strength steel bar was larger than that of the same high strength steel bar, only when the copper thickness was smaller than 0.5mm.
(c) Cast laminated bar of 60/40 brass and mild steel had a little larger fatigue strength comparing with adhesive-bonded one.
(d) Both cycles to failure and cycles to crack initiation of stainless clad steel increased with increment of stainless steel thickness. The stainless clad steel plate had larger fatigue strength than that of adhesive-bonded plate.
(e) Rolled laminated plate of 2.5% nickel steel and mild steel had a larger fatigue strength than that of mild steel plate and, in a certain stress range, it showed rather larger fatigue strength comparing with 2.5% nickel steel plate.