Bibliography: pages 117-120. / A high-speed reciprocating sliding wear test rig was used to examine the metal on metal surface interactions of materials under consideration for application in water powered stoping equipment. The suitability of this test rig was investigated by implementing a test programme covering self-mated stainless steel and stainless steel-on-bronze couples. These couples were examined under water lubricated conditions in a broad test matrix, covering sinusoidal peak velocities of 1, 5 and 10 m/s; loads of 5, 10 and 20N and surface roughness values ranging from 0.2 to 0.4 μm, CLA. Due to poor reproducibility and inconclusive wear behaviours, no inferences could. be made as to the relative performance of the couples tested and no ranking tables could be compiled, In response to these findings, the emphasis changed to the design of a better test facility which could more accurately simulate the tribological interactions of interest. A new laboratory test rig, capable of investigating the performance of material surfaces, rubbing against one another under conditions of high speed reciprocating sliding in specific environments, was designed, built and commissioned. Subsequent tests conducted on this new facility showed average reproducibility for a 122 stainless steel rubbing against a CZ114 manganese bronze to have improved by a factor of two to approximately ± 20%. Initial results confirmed that adhesive wear is the dominant wear mode for the materials under consideration. This is manifested by homogeneous transfer layers and subsequent grooving of these layers.

No description available.

Reliability analysis of series structural systems with emphasis on problems typical for metal fatigue is addressed. Specific goals include the following: (1) Given the distribution of strength of the components and the distribution of external loads on the system what is the probability of failure of the system? (2) Given the target safety index for the system, what would be the target safety index for the components? Exact solutions in the analysis of series structural systems only exists for some special problems. Some of these special problems are investigated. In particular some special cases of the problem of unequal element reliabilities are considered and some interesting observations are made. Numerical integration is in general required even when an exact solution exists. A correction or adjustment factor is developed for an important class of problems. This factor makes it possible to relate element and system probabilities of failure without numerical integration. However in most cases no exact solution to the structural series system problem exists. Approximations by for instance bounds on the probability of failure or Monte Carlo simulation has been the only way of approximating solutions. These two methods are generally not good approximation schemes since they are either too crude or too expensive. In this dissertation an approximation scheme for analysis of series systems where no exact solution exists is developed. The method only requires a simple numerical integration if the component safety index and the correlation coefficient between failure modes is known. Numerous examples are used to verify the method against known exact results and excellent estimates are obtained. Applications by practical examples is also given. In the appendix the problem of convergence of fatigue life distribution is also summarized.

No description available.

No description available.

No description available.

No description available.

No description available.

No description available.

No description available.