Microstructure and Mechanical Properties Essay Example | Topics and Well Written Essays - 750 words

Microstructure and Mechanical Properties - Essay Example In this process, a sapphire laser system is used to trap samples of the metallic material. The laser is set up to be able to emit a continuous wave at the infrared radiation on the spectrum at a wavelength of about 760nm. The back focal plane of the of the condenser is imaged on a quadrant photodiode for the measurement of position detection. The metal samples are placed on the stage of translation and to achieve this, two methods are used. Transmission can either be done from above using the light emitting diode (LED) or reflection from below using mercury. The fluctuation of the quadrant diode voltage and the traces of time are acquired through three channels including two radial dimensions and a single sum voltage trace used on all the diodes. The advantages of this process are that the Boltzmann’s distribution can be used to measure the radial dimension of the sample. It is also possible to measure the spectral density and the corner frequency of the sample. Spark plasma sintering method: This is a recently developed process. It is also referred to as the pulsed electric current sintering method. This method employs a DC current in pulses and this power is passed through an electrically conducting pressure die and finally through the ceramic sample under investigation. The die usually acts as the source of heat and the ceramic sample is then heated on both its outer surface and the inner surface. The ceramics that are nano crystalline in nature and have size 10-50nm are prepared through co-precipitation. For a pressure less sintering process, the composite ceramic is normally isostatically pressed into a cylindrical green compact at a pressure of 400 Mpa. All the samples are then cleaned using a sand paper in order to remove the outer layer that is contaminated with a layer of carbon. An x-ray diffraction is then conducted to determine the phase analysis