Adhesion between atomically clean metallic surfaces final report

Adhesion between atomically clean metallic surfaces - surface energy and bondin

Adhesion between atomically pure metallic surfaces, part iv semiannual report no. 2

Experimental investigation of physical adhesion, measurement of contact area during adhesion process, and effect of adsorbed or impurity species on metal-metal bondin

Adhesion between atomically clean surfaces

Adhesion mechanisms between solid metal surface

Adhesion between atomically pure metallic surfaces Final report

Metallic adhesion from compression loads resulting in plastic deformatio

Adhesion between atomically pure metallic surfaces, part 4 Semiannual report

Adhesion between atomically pure metal surface

Adhesion between automatically pure metallic surfaces, part 4 Semiannual report

Contact resistance measurements to determine adhesion between atomically pure metallic surface

Adhesion between atomically pure metallic surfaces, part IV Semiannual report

Adhesion between metal couples in vacuum environment and use of contact resistance measurements to evaluate surface contaminatio

Application of Recent Static Adhesion Data to the Adhesion Theory of Friction

Application of recent static adhesion data to adhesion theory of frictio

Effect of metallurgical structure and properties on adhesion and friction behavior of cobalt alloys

The metallurgical structure and some of the mechanical properties of two cobalt alloys, cobalt-50% iron and cobalt-25% molybdenum-10% chromium, were determined under various heat treated conditions. The mechanical properties of the bcc disordered Co-50Fe alloy, which was found to be very brittle, indicated an exceedingly low fracture strength, low hardness, and very weak grain boundary strength. Ordering by suitable heat treatment only produced a more brittle material with a lower fracture strength and a slightly higher hardness value. Work hardening was found to produce a finer grain structure and a greater grain boundary strength. Tensile properties were examined. It was found that the Co-25Mo-10Cr alloy was difficult to place in the alpha Co solid solution condition, which limited the ability to use precipitation as a hardening reaction. Over two hundred adhesion cycles from zero contact load, to maximum load, to fracture were conducted between couples for each of the above alloys in an ultrahigh vacuum system which would permit the sample surfaces to be cleaned of all contaminant layers. In the Co-50Fe case, the calculated fracture stress from the adhesion tests showed values in the range of 80 to 150 k.s.i., which is about ten times greater than the values from tension tests

X-Ray Diffraction and Reflectance Spectroscopy of Murchison Powders (CM2) After Thermal Analysis Under Reducing Conditions to Final Temperatures Between 300 and 1300c

The asteroids Ryugu and Bennu have spectral characteristics in common with CI/CM type carbonaceous chondrites and are target bodies for JAXAs Hayabusa2 and NASAs OSIRIS-Rex missions, respectively. Analog studies, based primarily on the Murchison CM2 chondrite, provide a pathway to separate spectral properties resulting space weathering from those inherent to parent-body, mineralogy, chemistry, and processes. Ryugu shares spectral properties with thermally metamorphosed and partly dehydrated CI/CM chondrites. We have undertaken a multidisciplinary study of the thermal decomposition of Murchison powder samples as an analog to metamorphic process that may have occurred on Ryugu. Bulk analyses include thermal And evolved gas analysis, X-ray diffraction (XRD), and VIS-NIR and Mssbauer spectroscopy; micro- to nanoscale analyses included scanning and transmission electron microscopy and electron probe micro analysisWe report here XRD and VIS-NIR analyses of pre- and post-heated Murchison powders, and in a companion paper report results from multiple electron beam techniques