Abstract: For an evaluation of the peel strength of a plastic sliding layer of a laminate for sliding surface bearings, which laminate comprises a steel backing, a porous sintered bronze layer on said steel backing, and a mixture of polytetrafluoroethylene which fills the pores of the bronze layer and constitutes a sliding layer on the bronze layer, the surface of the sliding layer of a sample that has been blanked from the laminate for sliding surface bearings is activated and adhesively joined to the end face of a testing bar of a testing apparatus in accordance with ISO Standard 4624. The ultimate tensile stress is then determined.

Abstract: In a composite casting process for making aluminum alloy components for internal combustion engines, which components are provided at highly loaded surfaces with shaped elements which consist of fibers or whiskers and are bonded to the castings, the shaped elements consisting of fibers of whiskers are infiltrated with an aluminum alloy which has a higher melting point than the aluminum alloy of the casting. The infiltration is effected in such a manner that the infiltrated aluminum alloy forms a cover layer on the shaped element. In order to ensure the formation of a bond between the casting and the shaped element as the aluminum alloy for making the casting is cast in contact with the shaped element, the infiltrated shaped elements are dipped into a molten solder alloy before the aluminum alloy for making the casting is cast in contact with the shaped element, and the latter is subsequently placed into the heated mold for making the casting, whereafter the casting is made.

Abstract: A light alloy piston for internal combustion engines has a skirt which is closed at its lower end and at locations disposed adjacent to the bosses on both sides of the horizontal plane through the piston pin is set back so as to form respective recesses. In order to avoid a retention of oil in the recesses those end portions of the skirt which adjoin the recesses are inwardly offset from the outside peripheral surface of the piston.

Abstract: A material which is intended for use in sliding surface bearings comprises a metallic backing, a porous metallic substrate layer applied to said backing, and a PTFE-filler mixture, which completely fills the pores of the substrate layer and constitutes an antifriction layer. The bond strength between the antifriction layer and the substrate layer is improved by coating that surface of the substrate layer which faces the antifriction layer with a primer.

Abstract: A composite bearing material for use in the manufacture of crankshaft bearings comprises a steel strip, which is provided on one side, which is to be used disposed on the outside of the bearing, with an elastic layer, and on the other side, which is to be disposed on the inside of the bearing, with a bearing metal layer. In order to effect a sound insulation, in a particularly desirable manner the elastic layer consists of halogen-free polymers.

Abstract: A cast light metal piston for internal combustion engines is provided with a ceramic insert in those zones which are highly thermally stressed and/or for heat insulation. To form a high-strength bond between the light metal and the insert, high-strength fibers are embedded in the light metal in the zone adjoining the insert.

Abstract: A composite piston for internal combustion engines has an interior cooling chamber and an outer cooling passage. An annular rib protrudes from the inside surface of the upper part and that surface of the lower part which faces that annular rib. An annular flange is clamped between said rib and said surface of the lower part. A tongue which protrudes into the cooling passage is provided on that edge of said flange which faces the cooling passage. In order to minimize the temperature of that surface of the cooling passage which is near the combustion chamber and to maintain at least adjacent to the uppermost ring groove a temperature which is sufficient to prevent a wet corrosion of the piston and of the piston rings, the tongue defines a relatively narrow annular gap with that surface of the cooling passage which is near the combustion chamber so that the coolant oil is throttled as it flows through that gap.