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Penggunaan kayu mersawa dan papan partikel sebagai material konstruksi bangunan dan tujuan dekoratif terus mengalami peningkatan. Penelitian sebelumnya menjelaskan bahwa material tersebut menghasilkan laju aus yang tinggi yang disebabkan oleh kandungan silika dan resin. Artikel ini menjelaskan karakteristik aus mata pisau yang telah dilapisi bahan pengeras baru pada pemotongan kayu mersawa dan papan partikel. Kayu mersawa dan papan partikel dengan kerapatan 0,8 dan 0,61 g/cm 3 dipotong menggunakan mata pisau tungsten carbide K10 yang telah dilapisi dengan lapisan tunggal titanium aluminium nitrid (TiAlN), multi-lapis TiAlN/titanium silikon nitrid (TiSiN), dan multi-lapis TiAlN/titanium boron nitrid (TiBN). Uji pemotongan menggunakan computer numeric control router pada kecepatan potong 17 m/s dengan laju pengumpanan sebesar 0,1 mm/rev untuk melihat karakteristik aus pada sisi clearance mata pisau. Hasil penelitian menunjukkan bahwa mata pisau yang telah dilapisi menghasilkan aus yang lebih rendah dibandingkan dengan mata pisau tanpa pelapis pada pemotongan kayu mersawa dan papan partikel. Lapisan multi-lapis TiAlN/TiBN pada penelitian ini menghasilkan daya tahan aus yang paling tinggi. Kekerasan yang tinggi, koefisien friksi yang rendah, daya tahan oksidasi yang tinggi, dan ketahanan terhadap delaminasi yang tinggi pada lapisan multi-lapis TiAlN/TiBN menunjukkan bahwa lapisan ini sangat cocok diaplikasikan pada pemotongan kayu abrasif (kandungan silika tinggi) dan kayu komposit pada kecepatan potong yang tinggi.

Ni-based superalloys are typically difficult-to-cut materials. During machining, the cutting forces and temperatures of these superalloys are generally higher than those of other materials. Therefore, the tool life of the coated carbide cutting tools used for superalloy machining is shortened. This study evaluates the damage of the coated end mills during interrupted cutting of alloy 718 and finds the coating properties necessary for improved cutting of Ni-based superalloys. Damage of the PVD-TiN-coated cutting tools was observed by scanning electron microscopy and transmission electron microscopy of the surfaces and cross sections. In addition, friction forces were measured during turning for some coatings, and hardness of the coatings was measured after annealing. Plastic deformation of the coating and crack formation was shown to occur at the coating cross section. In addition, we determined that the major factor for the damage was high friction force between the coating surface and work material at high temperatures. In summary, coatings with stability at high temperatures and low friction forces during machining can reduce the damage of coated cutting tools, thus increasing the tool life.

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For better selection of coated cutting tools, TiAlN (Ti50Al50N) and CrAlN (Cr50Al50N) coatings were deposited onto ball-nose and square end mills using arc evaporation, and their cutting performances were evaluated using steel workpieces of various hardnesses. In particular, cutting tests were performed on three types of workpieces, made from S50C, SKD61, and SKD11 steels, having Brinell hardness numbers of HB220, HRC40, and HRC60, respectively. The results of the cutting experiments were elucidated and discussed in terms of the mechanical properties and anti-oxidation resistances of the different coatings. The results revealed that TiAlN-coated square end mills at high cutting speeds (V = 200 m/min ) had superior performance when used on steels with high hardness (SKD11), whereas CrAlN-coated ball-nose end mills were superior when used on low hardness steel (S50C). Therefore, CrAlN-coated ball-nose end mills are concluded to be suitable for the machining of low hardness steels, whereas TiAlN-coated square end mills are preferable for the machining of high hardness steels (SKD11).

In this study, tool edge temperature was measured by a two-color pyrometer with an optional fiber. During one revolution of spindle, the tool edge passes over the fine hole at workpiece after cutting workpiece. An optical fiber inserted into the fine hole transmits infrared ray radiated from tool edge to two detectors with different spectral sensitivities. One peak signal from each detector can be obtained by each spindle revolution. The tool edge temperature can be calculated by taking the ratio of outputs from these two detectors. The relation between cutting heat calculated from cutting force and tool edge temperature was discussed. The tool edge temperature at the same cutting heat could be compared. The wet cutting condition caused lower tool edge temperature than the others at the same cutting heat. MQL and dry showed almost same tool edge temperature. The dispersion of tool edge temperature in wet cutting is wider than that in dry cutting and MQL cutting.