 The Vickers hardness test can cover an extensive range of test loads from several gram-force (gf) to 100 kilogram-force (kgf) with a single hardness scale. It is one of the most reliable strength tests because the simplicity of the testing theory and the indenter shape minimizes variances among hardness values obtained. The most vulnerable aspect of the Vickers method is an error when measuri...

A method for preparing and characterizing microencapsulated phase change materials (MPCM) was developed. A comparison with a commercial MPCM is also presented. Both MPCM contained paraffin wax as PCM with acrylic shell. The melting temperature of the PCM was around 21 °C, suitable for building applications. The M-2 (our laboratory made sample) and Micronal® DS 5008 X (BASF) samples were charact...

In this research, novel functionally graded Ni-P coating was deposited with electroless process. The content of phosphorus was controlled to change gradual through the thickness of the coating. During the plating, bath temperature and pH were changed at specified intervals to obtain functionally graded structure. To compare the properties of functionally graded coating with Ni-P single-layer co...

The development of Scanning Force Microscopy has provided us with tools to study friction and wear on the nanometer scale. The atomic granularity of matter shows up in the lateral force which is necessary to slide a small contact over a flat surface. Also, mechanical damage of a sample surface can be monitored with monolayer resolution [1]. The laws which determine the dependence of friction on...

It has become a feasible green building development strategy to prepare recycled aggregate concrete (RAC) by processing construction and demolition (C&D) wastes into coarse (RCA). On the other hand, defects such as low strength easy cracking of RAC seriously limit its application in materials. In this paper, RCA was strengthened pre-coated nano-silica (NS) slurry improve performance. The ef...

It has been proposed that with the appropriate models, instrumented indentation test (IIT) data can be reduced to yield the uniaxial stress–strain behavior of the test material. However, very little work has been done to directly compare the results from uniaxial tension and spherical indentation experiments. In this work, indentation and uniaxial tension experiments have been performed on the ...

The effects of environmental exposure upon the loadbearing properties of nine polyurethane foams commonly used for wheelchair cushion construction were studied. Test pieces with and without a stretch cloth cover were aged in the open air at Houston over the period April 26 to October 31, 1982. The indentation resistance of each piece was measured initially and at frequent intervals during the e...