Hironori Matsuoka

Fundamental Research on Hobbing with Minimal Quantity Lubrication of Cutting Oil Comparison of Cutting Performance with Dry Cutting

Abstract-This paper compares the cutting performance of minimal quantity lubrication (MQL) system with dry cutting in terms of flank wear, crater wear and finished surface roughness when using various kinds of cutting tools. Experiments were conducted by simulating hobbing by fly tool cutting on a milling machine. The results obtained are summarized as follows. (1) When using an uncoated tool, TiNand (Al, Ti) N-coated tools without coating on the rake face, and fully TiNand (Al, Ti) N-coated tools, MQL decreases the flank wear, crater wear and finished surface roughness compared with the wear and the roughness by dry cutting, particularly at the high cutting speed of 159 m/min. The reason suggested is the lubricating properties improved even with an extremely small quantity of cutting oil, which reduces the occurrence of deposited metal on the cutting edge. (2) With both the fully TiNand (Al, Ti) N-coated tools, the MQL system showed better cutting performance in terms of reduced tool wear and reduced finished surface roughness compared with that by dry cutting; in particular, the fully (Al, Ti) N-coated tool is suitable for an MQL system in hobbing.

Fundamental Research on Hobbing with Minimal Quantity Lubrication of Cutting Oil Influence of Hardness of Work Materials Under Several Cutting Conditions

This paper deals with the influence of hardness of work materials on flank wear, crater wear and finished surface roughness when using two types of high-speed steel (HSS) hob tool materials coated with (Al,Ti)N film. Specifically, hobbing with a minimal quantity lubrication (MQL) system is compared with dry hobbing. Experiments were conducted by simulating hobbing by fly tool cutting on a milling machine. The results are summarized as follows. (1) With SCM415 work material changed to hardness HB131, HB144 and HB161 by heat treatment, flank wear and crater wear of the tool are small when cutting comparatively hard HB161 work material, irrespective of the change in hob materials and cutting speeds. (2) With SCM435 work material changed to hardness HB172, HB195 and HB214, flank wear and crater wear tend to be small when cutting annealed HB172 work material. (3) When cutting SCM415 of hardness HB161 and SCM435 of hardness HB172, the finished surface roughness is small and the surface roughness of SCM415 is smaller than that of SCM435. (4) SCM415 of hardness HB161 is suitable for an MQL system in hobbing in terms of flank wear, crater wear and finished surface roughness.

Fundamental Research on Hob Materials.

In order to develop hob material which decreases wear, the influence of composition, heat treatment, hardness, and transverse rupture strength (TRS) of a hob on flank wear and crater wear was investigated in this paper. Experiments were carried out with a simple fly tool. Powder metal high-speed steel (PM-HSS) is better than normal HSS in decreasing wear. Among the materials tested, PM-HSS containing high vanadium and high cobalt performed best. The influence of heat treatment on hob wear is different according to the composition of the materials. At a low quenching temperature and a high tempering temperature for PM-HSS containing high vanadium and high cobalt, hob wear decreases. Corner wear and crater wear decrease with increasing hardness, and with decreasing TRS. Materials having more than 900 Hv hardness and 3 000 N/mm2 TRS are suitable for making hobs.

Effects of Cutting Speed, Cutting Fluid, and Carbon Fiber Orientation on Cutting of CFRP during Turning

This study examined the influence of cutting speed, cutting fluid, and pre-impregnated carbon fiber orientation on tool wear and finished surface roughness during turning of carbon fiber reinforced plastic (CFRP) pipes. In the dry cutting process, the tool wear decreased as the cutting speed was increased. An average cutting speed of 92 m/min or higher was found to be acceptable with respect to tool wear. The use of mineral oil resulted in a reduction of tool wear when compared with that in the case of dry cutting. The tool wear with water was lower than that with mineral oil. It was assumed that cooling by water was more effective than lubrication by mineral oil. The results clearly indicated that the tool wear and the finished surface roughness were affected by the carbon fiber orientation.

A study examining the effects of water-miscible cutting fluids for end milling process of carbon fiber reinforced plastic

This study examined the improvements to the tool life and finished surface roughness by using water-miscible cutting fluids in carbon fiber reinforced plastics end milling. In cutting tests, it was found that the use of emulsion type, soluble type, and solution type cutting fluids improved tool life compared with the case of dry cutting. Specifically, significant differences in tool life were observed at a high cutting speed of 171 m/min. In addition, the finished surface exhibited a low level of roughness when the solution type cutting fluid was used, regardless of the cutting speed.This study examined the improvements to the tool life and finished surface roughness by using water-miscible cutting fluids in carbon fiber reinforced plastics end milling. In cutting tests, it was found that the use of emulsion type, soluble type, and solution type cutting fluids improved tool life compared with the case of dry cutting. Specifically, significant differences in tool life were observed at a high cutting speed of 171 m/min. In addition, the finished surface exhibited a low level of roughness when the solution type cutting fluid was used, regardless of the cutting speed.

Influence of water-miscible cutting fluid on tool wear behavior of various coated high-speed steel tools in hobbing

This paper deals with the influence of water-miscible cutting fluid on tool life (flank wear) compared with that with dry cutting and water-insoluble cutting oil in hobbing. Experiments were conducted by simulating hobbing by fly tool cutting on a milling machine. The following results were clarified. (1) The water-miscible cutting fluid used in the test prolongs the tool life for TiN-, TiAlN-, TiSiN- and AlCrSiN-coated tools in comparison with that obtained by dry cutting and water-insoluble cutting oil. (2) It was presumed that the tool wear decreases and the tool life is improved by the lubrication effect of the synthetic lubrication additive, mineral oil and sulfuric EP additive contained in the water-miscible cutting fluid, and also by the cooling effect.

Effect of Cutting Oil Viscosity on Tool Wear Reduction in Turning Using an MQL System

The present paper describes the influence of the viscosity of cutting oil on tool wear and the roughness of the finished surface when using a cemented carbide tool in dry and minimal quantity lubrication (MQL) systems for turning. The following results were obtained. (1) At a feed rate of 0.2 mm/rev, the side flank boundary wear reduction effect was obtained with cutting oil having a low viscosity of 4.9 mm 2 /s in the MQL system, irrespective of cutting speed. The front flank boundary wear increased in MQL compared to dry cutting, and double boundary wear was observed. (2) At a feed rate of 0.4 mm/rev, cutting oil having a moderate viscosity of 9.3 mm 2 /s provided suitable side flank boundary wear, irrespective of cutting speed. (3) The front flank boundary wear obtained using the MQL system was greater than that for dry cutting. The transcription of the groove of this front flank boundary wear formed the finished surface roughness. KeywordsCutting; Turning; Dry; MQL; Viscosity Grade; Tool Wear; Finished Surface Roughness

Influence of Dimensions of Chip on Roughness of Finished Surface Produced by Hobbing (Fundamental Experiments Using Fly Tool)

©2013 The Japan Society of Mechanical Engineers 近年,機械加工において,切削性能の向上よりもむしろ作業環境の改善など環境問題に対する関心が高まって きており,環境に配慮したドライ加工やセミドライ加工技術の開発が行われている (1) ~ .ホブ切りにおいては, コーティング技術の発達により,ホブの耐熱性や耐摩耗性を向上させたコーティング膜が開発され,ドライホブ 切りが可能になり,環境保全および省資源の観点から強い関心が寄せられている.しかしながら,すべての歯車 材やホブ切り方法,ホブ切り条件,機械の剛性,熱影響,切りくず処理などに対応できるかを検討する余地があり, また,歯車の仕上げ面粗さや寸法精度などの点で多くの問題が解決されていない.これに対して,著者の一人は, ホブ切りを舞いツール切削にシミュレートし,ドライホブ切りに適した条件について報告している . 一方,セミドライ加工の代表である極微量油潤滑(MQL: Mnimal Quantity Lubrication)による加工は,環境に配 慮した加工法だけではなく,ドリル加工やリーマ加工など油剤が到達しにくい加工において良好な切削性能を発 揮し,またコストの面からも有利な加工法である.しかしながら,MQL によるホブ切りについての報告 (5)(6) があ る程度で非常に少ない.著者の一人は,ホブ切りを舞いツール切削にシミュレートし,MQL によるホブ切りの基 礎的研究について報告している . ホブ切りは平フライス削り形断続切削であり,その切削機構は複雑である.また,ホブの数刃が切削に関与し て歯溝部を削り取るが,各刃の切れ刃部で削り出される切りくず形状,すなわち切取り長さおよび厚さが異なっ Hobbing Fly tool cutting on milling machine 3-thread hob Feed of hob 4.0 mm/rev

Influence of Hob Materials on Behavior of Crater Wear of Hob in Dry Hobbing (Fundamental Experiments Using Coated Fly Tools without Coating on the Rake Face)

This paper investigates the influences of various high-speed steel hob substrates coated with (Al, Ti) N film, which are no coating on the rake face by grinding, on a behavior of crater wear mainly, flank wear and finished surface roughness in dry hobbing. Experiments were carried out using fly tools, which were made of normal high speed steels (HSS) and powdered metal high-speed steels (PM HSS). As a consequence, an interesting result was obtained that the crater wear with the M 34 HSS tool is smaller than that with the all PM HSS tools tested at a cutting speed of 117 m/min. At a high cutting speed of 159 m/min, though a failure took place at a tip of cutting edge in some HSS and PM IISS tools, a SK II 51 and a corresponding to SKH 55 HSS tools have no failure, and they are effective for the crater wear. The corresponding to SKH 55 tool, M 34 tool and the PM-HSS tools containing high vanadium and high cobalt are suitable in terms of the flank wear and the surface finished, irrespective of the change in the cutting speed.

Tool Wear Reduction Effect of Sulfonates as Additives in Cutting Oil for Hobbing. (1st Report). Influence of Sulfonates with Different Metal Types.

This paper deals with the influence of sulfonates having three kinds of different metal types on flank wear (tool life) and finished surface roughness in hobbing. Experiments were carried out using a fly tool. A sodium sulfonate decreases the flank wear of uncoated tool at a cutting speed of 117m/min, and a calcium sulfonate and a magnesium sulfonate are suitable for obtaining longer tool life with using a TiN and an (AI, Ti)N coated tool at cutting speeds of 117m/min and 159m/min, which are superior to the chlorinated fatty acid ester. The sulfonates used in the test improve the surface finish, which is smaller than that obtained with the chlorinated fatty acid ester. The use of sulfonates is effective for environmental pollution control and for improving the safety of the operator.