Abstract: An encapsulated actuator for testing specimens includes a housing contain a wall defining first and second chambers. The specimen under test is arranged in one of the chambers and vent holes are provided in the wall in order to equalize the pressure within the chambers. An actuator is arranged in the second chamber for generating a mechanical force and a force transmitting device is connected between the actuator and the specimen. The force transmitting device passes through an opening in the housing wall and transmits the mechanical force from the actuator to the specimen. Because the actuator is encapsulated within the housing, it is subjected to the same confining pressure as the specimen.

Abstract: A clamping device for applying loads to a test specimen including spherical egments connected to ends of the specimen. The spherical segments are in turn gripped by a race which allows pivotal movement of the segment. When the system is activated the race is gripped by the collet which is radially deformed by a circumferential clamp. When the spherical segment is clamped securely by the clamping device, the specimen may be axially or torsionally loaded by a reverse-direct stress testing device to determine physical properties of the specimen.

Abstract: Improved constant and variable force tensioning devices are made possible by utilizing atmospheric pressure to provide the restoring force. In one embodiment, a sealed and substantially evacuated canister is provided with a rigid actuating rod which can be partially withdrawn through an opening in one end of the canister against the constant restoring force exerted by atmospheric pressure. In another embodiment, the rigid actuator rod is replaced by a long flexible rod or cable which is capable of collapsing or folding upon itself within the canister, thereby providing the constant force device with a longer stroke. In a further embodiment, the actuator rod terminates in a rolling diaphragm seal which seals off only a portion of the canister interior, eliminating the need for a sliding vacuum seal at the point where the actuator rod protrudes from the canister.

Abstract: An improved apparatus is disclosed for measuring the adhesive bond strength etween two materials. A short, cylindrical specimen (28) having a test surface of one material is attached to a rigid base (12) on which a slide (16) is mounted on preloaded rollers (22) for movement along a pair of tracks (14) provided on the base. Above the specimen, a rigid mold block (36) is supported on an axially extending arm (24) formed integrally with the slide (16). The peripheries (32, 38) of the specimen and the mold block are essentially aligned so that seal ring (50) may be moved into engagement with a narrow gap formed between the specimen and the mold block. The second material, whose adhesive bond to the first material is to be determined, is introduced into the volume defined between the mold block and the specimen and caused or allowed to solidify there.