Integrated Design and Analysis of Diamond-coated Drills

Abstract

The objective of this paper is to investigate the drill geometry effects on the deposition residual stresses in diamond coated carbide drills, especially the interface stresses. The approaches include (1) solid modeling of diamond-coated two-flute twist drills using commercial computer-aided design (CAD) software, and (2) finite element analysis (FEA) to simulate residual stresses in a diamond-coated drill, which are generated during the deposition process due to the mismatched thermal expansion coefficients. It is noted that the residual stresses generated by deposition in diamondcoated drills can be significant, on the order of GPa. The modeling methodology is employed to design drills of different geometries. Further, to compare interface stresses around the cutting edge, 2D FEA is applied to simulate residual stresses of the drill cross-sections and the interface stress data at the drill cutting edge is transformed to quantitatively evaluate the drill geometry effects. The major results are summarized as follows. (1) The micro-level geometry such as the edge radius has the most dominant effects on the interface stresses by the deposition. (2) In particular, the radial normal stresses can become largely tensile, over 1.0 GPa, which may affect the coating adhesion integrity. (3) Changing the macro-level geometry such as the helix angle, point angle, and web-thickness will affect the wedge angle, 10 o to 20 o differences, at the drill tip. However, the effects on the interface stress magnitudes are rather minor.

Machining and Machinability of Fiber Reinforced Polymer Composites

“…In addition to the aforementioned and discussed simulation and analytical results of DGD, Miao et al (2009) studied the influences of drill design geometry on the deposition (interface) in a set of solid diamond-coated carbide twist drills, as shown in Fig. 2.15.…”

Fatigue Analysis of Actuators with Teflon Impregnated Coating—Challenges in Numerical Simulation

“…The fatigue module in MSC uses the three fatigue life prediction methods: total life, crack initiation, and crack propagation. Stress-life method Indentation test Yildiz et al [87] Stress-life method Fretting fatigue test Carlson et al [101] Strain-life method Material properties Navarro et al [102] Linear Fracture Mechanism Fretting fatigue test Alzoubi et al [68] Linear Fracture Mechanism Bending test Sangkla et al [103] Stress-life method Grippers Kolesnikov et al [104] Stress-life method Rails Sliwa et al [105,106] Stress-life method Coatings on steel Dobrzanski et al [107] Stress-life method Coatings on steel Wu et al [64] Stress-life method Ceramic coated steel Tasdemirci and Apalak [108] Stress-life method Indentation test Wei and James [82] Linear Fracture Mechanism Composite materials Sridhar et al [94] Temperature Piston Basecu et al [83] Stress-life method Wheel to wheel contact Bouzaki et al [88][89][90] Strain-life method Indentation test Kanber and Demirhan [93] Contact mechanics Thin to medium coating Majzoobi et al [109] Stress-life method fasteners Strain-life method Rolling and sliding contact Baregetti et al [110] Linear Fracture Mechanism PVD coating Baregetti [111] Linear Fracture Mechanism Coated spur gears Baragetti and Tordini [86] Strain-life method Rotating fatigue test Baragetti and Tordini [112] Strain-life method Spur gears Basecu et al [83] Stress-life method Wear at interface Ma et al [113] Stress-life method Coated carbide drill Miao et al [114] Hardness analysis Indentation test Ronkainen et al [115] Stress-life method Diamond-coated drills Mount [116] Linear Fracture Mechanism Thin-film coating Sheng [78] Contact mechanics Thin polymer films FEMLAB Lakkaraju et al [85] Stress-life method Indentation test Solid Works/Comos M Mituletu et al…”

A review of modern advancements in micro drilling techniques

“…To meet the current demand, not only the size of the micro drill but also a wide range of other parameters are being studied in order to enhance the performance of micro drills. In commercial manufacturing companies the focus is mainly on the size, shape and materials of the micro drill, while researchers attention falls on the investigation of mechanical properties [99,122], simulation and numerical analysis [58,123], micro drill parameter optimisation [50,124], surface texture of drills [69,125], chip formation analysis [28,64], lubrication methods [126,127], inspection mechanisms [128,129], resharpening processes [130,131], perforation techniques in different types of specimen [132,133], effects of coating [134,135] and prevention of tool breakage [95,136].…”