Thermal residual stress of polycrystalline diamond compacts

The aqueous electrophoretic deposition (EPD) of diamond–diamond laminates

“…By using Equation 5.3-1, it is estimated that the diamond table would have a compressive stress of about 755MPa. This value is close to the value obtained by Chen et al [49] who found through Finite Element Analysis (FEA) a maximum compressive stress at the interface to be 690MPa. [85] 0.32 [86] Since the physical properties of 0.5 and 2µm sintered diamond could not be found, the values were calculated by using the law of mixtures and the volume fractions of PCD Page | 124 and Co obtained by image analysis.…”

“…This is due to differences in thermal expansion coefficients [49]. In some cases this may lead to delamination of the diamond table from the substrate.…”

A Raman spectroscopy investigation into the influence of thermal treatments on the residual stress of polycrystalline diamond

“…In general, the measured Raman peaks were found to be lower than the unstressed single crystal value, indicating a resultant tensile stress due to processing. It is well documented that due to the mismatch in thermal expansion between diamond and the tungsten carbide substrates onto which they are sintered, the compressive residual stresses predominate within the diamond microstructure [3,6,9]. For reference, the residual stress across a typical PCD cutter was also determined in this study.…”

“…Similarly, Erasmus et al [7] conducted a study into the stress distribution within PCD samples as a function of geometry and temperature and found comparable levels of compressive residual stress. Chen et al [9] investigated thermal residual stresses in PCD cutters both experimentally and numerically and found the highest residual stress exists at the interface between the diamond layer and substrate. More recently, Kanyanta et al [10] demonstrated that appropriate choice of sintering conditions are required to reduce the transient stresses during the sintering process.…”

Perspective on Thin Film Waveguides for on-Chip Mid-Infrared Spectroscopy of Liquid Biochemical Analytes

“…One way to reduce the interfacial defects is to grow thicker films, as the film thickness increases the defect density reduces, and polish away the substrate to obtain low loss free-standing films . However, these films can be under high thermal residual stresses affecting their mechanical properties. , Moreover, single and polycrystalline films of diamond are grown using chemical vapor deposition (CVD) where the substrate is kept above 700 °C, which can be a problem to integrate with CMOS compatible processes.…”