Abstract: An evaluation method for monitoring the consequences of an impact at low speed and little force on a structural composite material part covered with a film that changes color when under pressure and whose color intensity is directly related to the force of a received shock.

Abstract: An evaluation method for monitoring the consequences of an impact at low speed and little force on a structural composite material part covered with a film that changes color when under pressure and whose color intensity is directly related to the force of a received shock.

Abstract: A fuel injection stub (6) for a ramjet is designed to operate at a high Mach number. According to the invention, said stub includes a carbon-carbon composite body (10), in which a rail of elementary injectors is arranged, and a nose piece (11) consisting of a thin skin of carbon-carbon composite in at least approximately the shape of a dihedron, the edge (11A) of which has a radius of curvature (r) at most equal to 2 mm and the angle of which is at most equal to 15.degree.. Means (23, 27) for injecting a coolant into the sealed chamber (18) are arranged in said body (10), said injection means producing a number of jets of pressurized coolant striking the concave face of said skin (11).

Abstract: The invention concerns a composit material with a glass-ceramic or ceramic matrix obtained by the sol-gel process and reinforced by fibers, wherein said matrix is MLAS matrix and wherein said fibers are at least 17% by volume Si-Ti-C-O fibers. FIG. 2 shows the flexural stress-strain curves (compression and tension) for a composite material containing 24% by volume of Si-Ti-C-O fiber in a MLAS matrix. Shaped articles produced from the composit material according to this invention can be used in the aeronautical and spatial industries and in motor vehicle engines.

Abstract: Apparatus for testing testpieces (11) in the form of small plates, in which the testpiece is grasped between two pairs of jaws (12,13), which can be moved together. The jaws (12,13) are mounted on the platens (1,4) without hyperstaticity, which reduces the risks of introducing parasitic forces. The testpiece can be notched in such a way that its median portion is exposed to shear. The jaws then have adequate lengths to cover the principal faces of the testpiece (11) virtually up to the notches. The shear field is at a maximum and quasi-uniform in the median surface between the notches. This invention is useful for characterizing the interlaminar shear of plates made from composite materials and includes curved testpieces.