Abstract: A ring for protecting the edge of a combustion bowl disposed within a top surface of a light-alloy piston for a diesel engine. The ring is made of fine-grain carbon and serves as bowl edge armor. The ring is galvanically coated before being bonded to the remainder of the piston. The exterior surface of the bowl edge armor is coated with an antioxidation compound.

Abstract: In a process for cleaning short mineral fibers in which the fibers contaminated with foreign bodies are separated from the foreign bodies, at least starting with a certain size, whereby mechanical damage to the fibers is avoided. For this purpose, the crude fiber material to be cleaned is added to a carrier medium which is set in a flowing motion and subsequently passed along a separation apparatus with at least one slot-like recess in the direction of the longitudinal extension of the recess. Thus, at least part of the carrier medium passes from an upstream side through the recess, together with the fibers, to a downstream side. In this way, a fiber filtrate is produced, of which the degree of purity is solely determined by the width of the recess. The carrier medium mixed with the crude material can be circulated in the cleaning process, with the carrier medium separated from the clean fiber filtrate being continuously returned to said circulation as well.

Abstract: In an internal combustion engine, a piston has forged sections made of steel, especially in the piston head area, as well as at the hubs, and areas made of light metal, especially in the area of the piston skirt. The previously used quenched and drawn steel 42CrMo4V is to be replaced with a steel that has comparable properties but is more cost effective to manufacture. This replacement steel is a precipitation hardened ferrite-perlite steel.