알루미나 세라믹의 초음파가공 특성 연구

강익수,강명창,김창식,김광호,서용위,Kang, Ik-Soo,Kang, Myung-Chang,Kim, Jeong-Suk,Kim, Kwang-Ho,Seo, Yong-Wie 한국기계가공학회 2003 한국기계가공학회지 Vol.2 No.1

Engineering ceramics have many unique characteristics both in mechanical and physical properties such as high temperature hardness, high thermal, chemical and electrical resistance. However, its machinability is very poor in conventional machining due to its high hardness and severe tool wear. In the current experimental study alumina($Al_2O_3$) was ultrasonically machined using SiC abrasives under various machining conditions to investigate the material removal rate and surface quality of the machined samples. Under the applied amplitude of 0.02mm, 27kHz frequency, three slurry ratios (abrasives water by weight) of 11, 13 and 15 with different tool shapes and applied pressure levels, the machining was conducted. Using the mesh number of 240 abrasive, slurry ratio of 11 and static pressure of $25kg/cm^2$, maximum material removal rate of $18.97mm^3/mm$ was achieved with mesh number of 600 SiC abrasives and static pressure of $30kg/cm^2$, best surface roughness of $0.76{\mu}m$ Ra was obtained.

고속 머시닝센터의 진동특성 및 가공성 평가

강익수,강명창,김정석,김기태 한국공작기계학회 2004 한국공작기계학회 춘계학술대회논문집 Vol.2004 No.-

The high speed machining center(HMC) has been widely applied to manufacture a die and trial product in many machine industry. Because the evaluation for HMC is not sufficiently performed and the efficient cutting conditions can't be selected, a great loss has been caused in the cost aspect. In this study, the need of preliminary running time and unstable spindle speed is presented by the analysis of acceleration in idling. The Machinability for the TiAIN coated flat end mill and STD11(H_(R)C60) is evaluated from the trends of tool wear and cutting force according to cutting conditions. The resonance spindle speed is identified through the tool wear and natural frequency test.

Cutting force model considering tool edge geometryfor micro end milling process

강익수,Jeong Suk Kim,Yong Wie Seo 대한기계학회 2008 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.22 No.2

The analysis of the cutting force in micro end milling plays an important role in characterizing the cutting process, as the tool wear and surface texture depend on the cutting forces. Because the depth of cut is larger than the tool edge radius in conventional cutting, the effect of the tool edge radius can be ignored. However, in micro cutting, this radius has an influence on the cutting mechanism. In this study, an analytical cutting force model for micro end milling is proposed for predicting the cutting forces. The cutting force model, which considers the edge radius of the micro end mill, is simulated. The validity is investigated through the newly developed tool dynamometer for the micro end milling process. The predicted cutting forces were consistent with the experimental results.

세계화 시대 전인교육을 위한 교육과정의 과제

강익수 한국교육과정평가원 2008 교육광장 Vol.28 No.-

리더쉽 理論

姜益秀 慶北大學校 經營大學院 1988 最高經營者課程 論文集 Vol.- No.7

안경테용 새로운 셀룰로오스 아세테이트 소재의 고품위 가공을 위한 절삭성 평가

강익수,최현진,이승용,이태호,고영준,김기홍 대한시과학회 2012 대한시과학회지 Vol.14 No.4

Purpose : The aim of this study is to investigate the machinability of developed novel cellulose acetate(CA) for improving the machined quality and productivity. Methods :The machinability is evaluated under various cutting conditions with cutting speeds and feeds. Cutting experiments of CA are conducted to investigate the machinability in terms of cutting forces, surface roughnesses, and chip formations. Result :The cutting forces are low at higher speeds except for 20,000 and 30,000 rpm. The surface roughnesses at higher cutting speed conditions are better than that of lower speed conditions. The correlation between the cutting force and the surface roughness at high speed conditions is not sufficient. Conclusion :The machinability of developed CA for spectacle frames were discussed in terms of the cutting forces, surface roughnesses, and chip formations. The machinability is improved at high speed and low feed conditions. A machinability criteria using the experimental results is proposed in this study. 목 적 : 본 연구의 목적은 새롭게 개발하여 국산화한 안경테용 셀룰로오스 아세테이트(Cellulose Acetate; CA) 소재의 가공품질 및 생산성 향상을 위해 절삭성에 관한 연구를 수행하였다. 방 법 : 다양한 절삭 및 이송속도의 변화조건 하에서 절삭성이 평가되었다. CA 소재의 절삭실험은 절삭력, 표면조도 및 칩형상 등의 분석이 이루어졌으며, 이를 통해 절삭성을 평가하였다. 결 과 : 주축회전수 20,000과 30,000 rpm을 제외하고 고속영역에서 절삭력이 낮게 나타났으며, 고속회전 시 표면조도가 저속회전 조건 보다 우수하였다. 절삭력과 표면조도의 상관관계는 고속회전 조건에서는크지 않은 것으로 나타났다. 결 론: 국산화를위해새롭게개발한안경테용CA 소재의고품위가공의절삭성평가를수행한결과주축회전수20,000과30,000rpm을제외하고고속영역에서절삭성이양호하였으며, 표면조도는날당이송0.1mm 이외의 조건에서 주축회전수가 증가할수록 양호해졌고, 칩형상도 고속회전 및 저이송 조건으로 갈수록 균일한 형태의 칩이 발생됨을 알 수 있었다. 이상과 같은 실험결과를 종합하여 새롭게 개발된 CA 소재의 절삭성을 평가할 수 있는 기초자료를 확보할 수 있었다.

사출금형의 5축 고속가공에서 공구자세에 따른 가공 특성에 관한 연구

강익수,김석원,김정석,이기용 한국공작기계학회 2006 한국공작기계학회 추계학술대회논문집 Vol.2006 No.-

The high speed machining has been widely applied to manufacture a die and machine elements product in industrial field. Especially, 5-axis milling has been employed to produce a wide range of turbine blades, impellers and complex molds. In this study, machining characteristics of injection mold was investigated according to tool position control. The cutting force and surface roughness were measured with various tool position angles. When the tool position angle was over 25 degree, the cutting force was decreased and surface roughness was good compared with low tool position angles.

Development and Evaluation of Tool Dynamometer for Measuring High Frequency Cutting Forces in Micro Milling

강익수,김전하,홍진숙,김정석 한국정밀공학회 2010 International Journal of Precision Engineering and Vol. No.

A tool dynamometer is developed for measuring the high frequency cutting forces, and evaluated in micro milling of aluminum 6061-T6 using a tungsten carbide (WC) micro end mill. To improve the accuracy and productivity of the machining process, it is essential to monitor and control the machining process by measuring cutting forces. In order to improve the precision and quality of machined parts, high-speed machining with smaller micro tools is required, causing higher frequency cutting forces. The first natural frequency of tool dynamometers is high enough to precisely measure the high cutting forces. We investigate dynamic characteristics of the tool dynamometer theoretically and experimentally. The measurable frequency range of the developed tool dynamometer was higher than the commercial tool dynamometer, and the measured cutting force signals were not distorted at high-speed of above 60,000 rpm. The results showed that the developed dynamometer is able to measure the static and dynamic force components in high-speed micro milling.

학습자의 진로를 고려한 IB Diploma 이수모형에 관한 연구

강익수,박하식,홍후조 한국교육과정학회 2007 교육과정연구 Vol.25 No.3

안경테 소재용 셀룰로오스 아세테이트의 가공성 평가

강익수,최현진,이승용,이태호,고영준,김기홍 대한시과학회 2011 대한시과학회지 Vol.13 No.4

Purpose: The objective of this study is to investigate proper machining conditions of cellulose acetate(CA) for eyewear frames. The results are able to be applied to design the high-speed machine tool of CA frame. Methods: Cutting forces, surface roughnesses, machined surface shapes and chip formations are investigated to evaluate the machinability of CA. The proper machining conditions are selected through various machining tests with cutting speeds and feed rates. Results: Feed-direction cutting forces are increased at high-speeds of 20,000 and 30,000 rpm. On the other hand, radial-direction cutting forces are independent upon the cutting speeds. The surface roughnesses of higher cutting speed conditions are better than that of lower speed conditions when the feed per tooth is 0.05 mm. Conclusions: The machinability of CA materials were discussed in terms of the cutting forces and surface roughnesses. The cutting speed of 25,000 rpm is the proper machining condition considering the cutting forces. At the small feed per tooth of 0.05 mm the conditions between 20,000 and 30,000rpm are recommended considering the surface roughnesses and chip formations. 목 적: 본 연구는 안경테 소재용 셀룰로오스 아세테이트(Cellulose Acetate; CA)의 최적 가공조건을 규명하여 안경테 전용 가공기의 설계조건 선정에 활용하고자 한다. 방 법: CA안경테 소재의 가공성 평가를 위해 절삭력, 표면조도 및 형상, 칩 형상 등을 분석하였다. 절삭속도와 이송속도를 가공변수로 다양한 실험을 수행하여 적정 가공조건을 선정하였다. 결 과: CA안경테의 반경방향 절삭력은 절삭속도에 변화에 따른 영향이 미미한 반면, 이송방향 절삭력은20,000과 30,000 rpm에서 증가하는 경향을 보였다. 표면조도는 날당 이송이 작은 0.05 mm 경우 절삭속도가 증가하면서 양호해지는 결과를 얻었다. 결 론: 안경테 소재용 CA의 가공성을 절삭력과 가공면의 상태를 고려하여 평가하였다. 절삭력을 고려했을 때 절삭속도가 25,000 rpm이 가장 적정한 조건으로 나타났다. 표면조도를 고려했을 경우에는 저 날당 이송, 고 절삭속도가 최적 가공조건이었다. 따라서 이를 종합했을 때 절삭력은 전체적으로 낮은 값을 가지므로표면조도를 주요 인자로 고려하여 날당 이송 0.05 mm, 절삭속도 20,000~ 30,000 rpm이 적정 가공조건으로 나타났다.