摘要:
A fibrous carbon material is first coated with a thermosetting material which remains flexible after being subjected to curing temperatures. The thermosetting material contains a refractory metal capable of reacting with boron to form a metal boride. This thermosetting resin is then cured. The fibrous carbon material is then impregnated with a second thermosetting resin containing a boron compound and, optionally, a refractory metal capable of reacting with boron to form a metal boride. The second thermosetting resin is at least partially cured and a plurality of layers of the fibrous material is then assembled to form a laminate. The laminate is heated to a temperature sufficient to carbonize the thermosetting resin. The resultant carbon-carbon composite has better oxidation resistance, improved high temperature stability, higher density and improved interlaminar tensile strength than does a composite prepared without the presence of the refractory metal in the thermosetting resin.
摘要:
This invention relates to carbon--carbon (C--C) composite comprising carbon fibers or carbon fabric, carbon char on the carbon fiber or fabric and pyrolytic carbon on the carbon char, wherein the density of the carbon composite is at least 1.3 g/cc. The invention also relates to wet friction elements and power transmission devises containing the same. The invention also relates to methods of preparing the carbon--carbon (C--C) composites. These C--C composites and wet friction elements and power transmission devises made therefrom have improved friction properties desired by wet brakes and clutches. These C--C composites provide improvements in cost, and when run against metals, such as steel or iron, improvements in wear and frictional behavior compared to known C--C composites for wet friction applications. In one aspect, the carbon--carbon does not require bonding to a metal backing or core material.
摘要:
There is disclosed the reaction product of an epoxy resin and a metal complex which is a reaction product of tungsten carbonyl and/or molybdenum carbonyl with pyrrolidine.