Abstract: A piston ring (22) is covered at least partially with a layered structure (30). The layered structure (30) comprises: —a first intermediate layer (32) comprising at least one element of group IVB, group VB or group VIB; —a second intermediate layer (34) deposited on top of the first intermediate layer (32) and comprising a diamond-like nanocomposite composition; —a diamond-like carbon layer (36) deposited on top of the second intermediate layer (34).

Abstract: A piston ring (22) is covered at least partially with a layered structure (30). The layered structure (30) comprises: —a first intermediate layer (32) comprising at least one element of group IVB, group VB or group VIB; —a second intermediate layer (34) deposited on top of the first intermediate layer (32) and comprising a diamond-like nanocomposite composition; —a diamond-like carbon layer (36) deposited on top of the second intermediate layer (34).

Abstract: This invention relates to a novel valve useful in internal combustion engines and other engines having improved wear and corrosion properties. The valve has a uniform coating thereon containing nickel and having a thickness not exceeding 0.000500 inches. The coating must be substantially uniform in thickness throughout its extension.

Abstract: The novel valve of this invention is for use in internal combustion engines. With advanced engine technology of today, prior art valves are not suitable because of wear problems. The valve of this invention provides a valve stem texture that is smooth enough to cause minimal wear on contacting parts while at the same time rough enough to retain sufficient oil to lubricate the parts. This is accomplished by having a stem surface with a surface peak height of Rp 4.0 to 15.0 and cross hatching on the affected surface portions. The cross hatching has a depth having an Rvk value of up to 30 micro-inches.