An SiCf/SiC composite has the following excellent properties: high strength, low specific gravity, and temperature resistance, which great prospects in combustion chamber of rockets or aero engines. Hole-making parts is an important processing method. Generally, water-based oil-based coolants are avoided, so dry drilling primary hole-making approach for SiCf/SiC. However, abrasion resistance ha...

Advanced Ceramics find wide range of industrial applications. Cutting of advanced ceramic (SiC) is very difficult using conventional machining methods due to its low fracture toughness. In the past few years, researchers have claimed successful machining of ceramic composites using EDM process. Furthermore, increasing trend, necessity of miniaturization, micro components in MEMS and semiconduct...

In the last years, laser beam drilling became increasingly important for many technical applications as it allows the contactless production of high quality drill holes. So far, mainly short laser pulses are of industrial relevance, as they offer a good compromise between precision and efficiency and combine high ablation efficiency with low thermal damage of the workpiece. Laser beam drilling ...

[1] As part of the Hawaii Scientific Drilling Project (HSDP), an exploratory hole was drilled in 1993 to a depth of 1056 meters below sea level (mbsl) and a deeper hole was drilled to 3098 mbsl in 1999. A set of geophysical well logs was obtained in the deeper hole that provides fundamental information regarding the structure and the state of stress that exist within a volcanic shield. The acou...

Engineering plastics have specific properties in strength, hardness, impact resistance, and aging persistence, often used for structural plates electronic components. However, the holes made by drilling process always shrink after cutting heat dispersion due to their high thermal expansion coefficient. Drilling parameters must be discussed thoughtfully especially small-hole fabrication acquire ...

Abstract Background While near surface residual stress (NSRS) from milling is a driver for distortion in aluminum parts there are few studies that directly compare available techniques NSRS measurement. Objective We report application and assessment of four different evaluating versus depth milled parts. Methods The are: hole-drilling, slotting, cos(?) x-ray diffraction (XRD), sin 2 (?) XRD, al...

Rotary ultrasonic machining (RUM) is a nontraditional drilling process. It has been used to drill not only brittle but also ductile materials. It was observed that the surface roughness of the drilled hole near the entrance side was better than that near the exit side. However, explanations about this observation could not be found in the literature. This paper aims to provide explanations abou...

During Leg 59 of the Deep Sea Drilling Project, five sites (447 to 451) were occupied and seven holes drilled between Okinawa and Guam in the Philippine Sea (Fig. 1). All holes except Hole 447 yielded common calcareous nannoplankton at certain intervals cored. Nannoplankton assemblages and their age assignments will be discussed for each site, and fossil lists for selected samples from Holes 44...

In rotary drilling operation, the hydraulic circuit typically consists of stand pipe, rotary hose, swivel, Kelly, drill pipe, drill collar, drill bit, and the annulus between the drillstring and the open hole or the casing. Stand Pipe Pressure, abbreviated as SPP, is defined as the total frictional pressure drop in the hydraulic circuit. SPP, an important drilling parameter in selecting proper ...

Bone drilling is one of the most common operations used to repair fractured parts of bones. During a bone drilling process, microcracks are generated on the inner surface of the drilled holes that can detrimentally affect osteosynthesis and healing. This study focuses on the investigation of microcracks and pullout strength of cortical-bone screws in drilled holes. It compares conventional surg...