Abstract: A method and system for lubricating a positive displacement machine operating as an expander of a compressed gas, comprising introducing into an expansion chamber of the machine a lubricant whose pour point temperature is greater than the operating temperature of the machine in the expansion chamber as determined by the expanding gas, which thus causes the lubricant to freeze-adhere to the internal surfaces of the expansion chamber, to become fluid under increased pressure at a point of contact of the working surfaces of the expander and then to refreeze when the surfaces separate. Considerable reduction in the quantity of lubricant is realized with the attendant advantage that dis-entrainment of lubricant from the gas exhausted from the machine is largely avoided.

Abstract: A method for forming a ceramic containing composite structure is proposed comprising the steps of (a) feeding a ceramic component that sublimes and a metallic or semi-conductor material that does not sublime into a thermal spray apparatus, (b) spraying the ceramic component and the metallic or semi-conductor material onto a substrate, whereby the ceramic component and the metallic or semi-conductor material deposit on the surface of the substrate, and (c) keeping the metallic or semi-conductor material on the substrate surface plastic during spraying at least in the region where the metallic or semi-conductor material actually strikes the surface.

Abstract: A method and system for lubricating a positive displacement machine operating as an expander of a compressed gas, comprising introducing into an expansion chamber of the machine a lubricant whose pour point temperature is greater than the operating temperature of the machine in the expansion chamber as determined by the expanding gas, which thus causes the lubricant to freeze-adhere to the internal surfaces of the expansion chamber, to become fluid under increased pressure at a point of contact of the working surfaces of the expander and then to refreeze when the surfaces separate. Considerable reduction in the quantity of lubricant is realised with the attendant advantage that dis-entrainment of lubricant from the gas exhausted from the machine is largely avoided.

Abstract: The invention relates to a thermal spray feedstock composition that employs free flowing agglomerates formed from (a) a ceramic component that sublimes,(b) a metallic or semi-conductor material that does not sublime and (c) a binder. The invention also relates to a method for preparing the agglomerates and a method for preparing ceramic containing composite structures from the agglomerates.

Abstract: A method for forming a ceramic containing composite structure is proposed comprising the steps of (a) feeding a ceramic component that sublimes and a metallic or semi-conductor material that does not sublime into a thermal spray apparatus, (b) spraying the ceramic component and the metallic or semi-conductor material onto a substrate, whereby the ceramic component and the metallic or semi-conductor material deposit on the surface of the substrate, and (c) keeping the metallic or semi-conductor material on the substrate surface plastic during spraying at least in the region where the metallic or semi-conductor material actually strikes the surface.

Abstract: The invention relates to a thermal spray feedstock composition that employs free flowing agglomerates formed from (a) a ceramic component that sublimes,(b) a metallic or semi-conductor material that does not sublime and (c) a binder. The invention also relates to a method for preparing the agglomerates and a method for preparing ceramic containing composite structures from the agglomerates.