鹽浴窒化處理溫度에 依한 疲勞强度의 變化에 關한 硏究

남궁척,李載元,朴鍾鎬 충남대학교 공업교육연구소 1978 論文集 Vol.1 No.2

In these experiments, We studied the relations between the nitriding temperature of salt bath and the fafigue strength due to alternating bending tests of sorbites, SCM_4 and SK_5 which had been subjected to nitriding. The results obtained were as follows; The maximum fatigue limit was obtained at about 600℃ of nitriding temperature for SCM_4 and about 575℃ for SK_5. The relations between Fatigue strength and any of surface hardness, depth of hardening, compound layer, residual stress, etc. due to nitriding at various temperatures were examined. As the results, The fatigue strength was likely to increase with the increase in surface in surface hardness, and the susceptiility to brittle rupture increased with increase in thickness of hardening depth, which led to the decrease in fatigue limit.

Random Exciting에 依한 드릴링머시인의 動的性能試驗에 關한 硏究

남궁척 충남대학교 공업교육연구소 1983 論文集 Vol.6 No.2(B)

In this study, both cutting tests and exciting tests were conducted to establish the basis for dynamic performance tests of drilling machines. For the cutting test, the behavior of the static and dynamic components of cutting resistance in drilling were measured with a dynamometer of the piezoelectric transducer type. For the exciting test, the machine tool was excited through an excitor and the displacement caused by the exciting force was measured, The exciting signals used in the exciters were analogous signal and cutting resistance signal. The testpieces used in the experiments were carbon steel, brass and aluminium alloy. On the basis of the results of the experiments, the following conclusions are drawn; 1. Static and dynamic components in drilling. 1) Dynamic components of cutting resistance were not related to the depth of drilled hole. 2) As feed and drill diameter increased, static and dynamic components of cutting resistance were increased. 3) Dynamic components of cutting thrust were increased by increasing spindle speed. 4) The ratio of the dynamic component to the static component was 0.3-0.5 in torque and 0.1-0.2 in thrust. 5) The behavior of the static and dynamic components in the process of drilling through was the same as that of a blind hole. 6) The characteristics of the tool system affected the dynamic component of cutting resistance greatly, though this effect depended considerably on the work materials. 7) The maximum amplitude of the dynamic componet was increased in proportion to the feed rate and the spindle speed. 2. Exciting test of drilling machines. I) The frequency respone of Inertance of a drilling machine, measured by using analogous random signal as an exciting source, was different from that of the signal of cutting resistance. 2) Even though actual drilling conditions were used for the exciting signal, the measured results were different, depending on the drilling conditions and work materials. In the case of the exciting test, better results could be obtained when a cutting resistance signal was used as an input for the exciting signal and the peformance of the drilling machine could be tested under practical drilling conditions.

알미늄과 그 合金의 熔接金屬의 機械的 性質에 關한 硏究

남궁척,金澤基 충남대학교 공업기술개발연구소 1976 工業技術開發硏究所論文集 Vol.3 No.2

The relation between the mechanical properties and the macrographic structures of pure Al and it's alloy TIG welded under the different welding velocities ranging from 100 mm/min to 1000 mm/min and constant electric power was investigated. The mechanical properties of these specimens were measured by Vicker's micro-hardness tester and tensile testing machine, and the structure were observed with the metallurgical microscope. The following results were obtained; 1. The tensile strength is not related to the welding velocity and growing direction of the columnar crystal. 2. The growing direction of the columnar crystal influences on the elongation. 3. The tensile strength shows a tendency to increase with increasing equiaxed dendrite. 4. The hardness is increasing from center of welding parts (Hv40) to the base metal (Hv52).

熔接部의 Coil式 磁粉探傷法에 關한 硏究 : 疑似模樣을 中心으로

남궁척,朴鍾鎬 충남대학교 1977 工業技術開發硏究所論文集 Vol.4 No.2

In case of inspecting the defect of the welding part by the magnetic inspection test, in order to trace to its origin, the hardness of the sample and the distribution of the deposited metal element have been systematically investigated. The sample, SS41 steel plates were welded by the home-made electrode, W-1, W-2, W-3, W-4, W-5. Vicker's Micro hardness Tester for the hardness, the magnetic particle inspection test was used to inspect the magnetic particle appearance. The following results were obtained; 1. Regardless of the welding electrode, hardness was rapidly increased in proportion to the inner zone of the deposited metal. Especially the W-3 deposited metal was very larger than the hardness of the base metal. 2. The magnetic particle appearance could be seen the fusion boundary, this was investigated that the appearance was not the effect of the welding defect but the difference of the susceptibility of the base metal and the deposited metal.

용해로 조업(操業)에 관한 고찰(考察)

南宮척 大田工業高等專門學校 1970 論文集 Vol.6 No.-

The cupola is the oldest type of furnace and the most economical. It may be operated for as long a time as may be regired to produce a given amount of melted metal. It is difficult to produce metal of precisely uniform quality in the cupola as compared to furnaces in which uniformity of the molten material can be controller by frequent and periodic tests and adjustments. The experience of a skilled operator is required to regualate the quality of the metal in a cupola. A research on how to operate a cupola is as follows ; 1. repair of a cupola; It is normal practice to clean and repair the cupola after each time it has been used. 2. melting method; Explanation of the complete operation of a cupola will be divided into three phases; cleaning and preparation of the cupala, the lighting-up operation, and the melting operation.

Drill 加工에 있어서의 切削抵抗의 動的成分에 關한 硏究(Ⅰ)

남궁척 충남대학교 공업교육연구소 1982 論文集 Vol.5 No.1

In this study, the static and dynamic components of cutting resistance were measured by tool dynamometer(swiss, piezo-electric type) when S45C, Al-alloy and brass were drilling under the some variable conditions. The results obtained are as follows; 1) The dynamic components of these cutting resistance are not related to the depth of drilled hole. 2) The static and dynamic components of cutting resistance are increased in accordance with the increase of feed and drill diameter. 3) The dynamic components of thrust force are increased in accordance with the increase of spindle speed. 4) The rate of the dynamic component to the static component is 0.3∼0.5 in torque, 0.1∼0.2 in thrust force. 5) The characteristic of the tool system is affected in dynamic component of cutting resistance, and the created frequency and amplitude of the chip are determined by the drilled materials. 6) The maximum amplitude of the dynamic component is increased proportionally in accordance with the feed rate and the spindle speed.

實驗機器의 效率的인 活用을 위한 敎授-學習資料의 開發

姜理錫,남궁척,鄭秀永,權赫茂 충남대학교 공업교육연구소 1983 論文集 Vol.6 No.2(A)

In this study, teaching-learning processes were reviewed and instructional materials were developed on 15 different tasks and subjects through the combined efforts of 4 departments. Experimental manuals were developed for every tasks and subjects and audio-visual supportive materials, slides, OHP's and models, were made to promote the complete teaching-learning. Tasks and subjects for developed instructional materials are as follows; 1) Sawing on the radial-arm saw. 2) Sawing on the circular, or table, saw. 3) Sawing on the band saw. 4) Sawing with the portable electric handsaw. 5) Planing for thickness. 6) Planing on the jointer. 7) Shaping on the shaper and the router-shaper. 8) Sanding on the sanding machines. 9) Sanding with portable electric sanders. 10) Drilling holes with portable electric drills. 11) Melting practice of cast iron by high frequence induction melting. 12) Method for determining compression strength for foundry sands. 13) NC lathe operation and programming experiment. 14) Electric discharge machine operation and machining experiment. 15) Air flow demonstration experiments.

旋盤을 利用한 炭素鋼 麻擦熔接의 機械的 性質에 關한 硏究

閔宅基,남궁척 충남대학교 공업교육연구소 1980 論文集 Vol.3 No.1

In this study, hardness, tensile strength and bending strength of carbon steel in friction welding by use of lathe were observed as follows; 1. The optimum revolution of lathe was found at 1,860 r.p.m. in the fixed conditions of 15kg/cm²of heating pressure, 25kg/cm²of upset pressure and 3.5 seconds of upset time. 2. The hardness of test pieces were increased in weld interface and were decreased in the boundary of 2∼4mm distance from weld interface. 3. Tensile strength and bending strength were increased as compared with original materials.

切削抵抗의 動的成分에 미치는 切削條件의 影響에 關한 硏究(Ⅱ)

全彦燦,남궁척 충남대학교 공업교육연구소 1986 論文集 Vol.8 No.3

In this study, the static and dynamic commponents of cutting resistance were measured with tool dynamometer (Swiss, piezo-electric type) when S 45 C, Al-alloy and brass were drilled under the some variable conditions. 1) The dynamic components of these cutting resistance are not related to the depth of drilled hole. 2) The static and dynamic components of cutting resistance are increased in accordance with the increase of feed and drill diameter. 3) The dynamic components of thrust force are increased in accordance with the increase of spindle speed. 4) The rate of the dynamic component to the static component is 0.3∼0.5 in torque, 0.1∼0.2 in thrust force. 5) The characteristic of the tool system is affected in dynamic component of cutting resistance, and the created frequency and amplitude of the chip are determined by the drilled materials. 6) The maximum amplitude of the dynamic component is increased proportionally in accordance with the feed rate and the spindle speed.

工業高等學校 機械科 敎育方向設定에 關한 硏究

徐大敎,宋周鎬,남궁척,朴鍾鎬,閔宅基 충남대학교 공업교육연구소 1979 論文集 Vol.2 No.2

The Korean Ministry of Science and Technology announced a long-term demand suppley programs of man power, in which we should train about 1,800,000 technicians between 1973 and 1981. The technical high schools are charged with the education. of 840,000 technicians. This paper is a proposal for an improved course of education in the mechanical departments of technical high schools. All kinds of typical high schools with mechanical departments were visited and the directors and techers were consulted regarding their education courses. Questionaires were mailed to technical high schools and key enterprises to determin the present situations of the students and graduates from their many-sided viewpoints. The findings, in brief, are as follows: 1. All students should work in industry for 6 months. 2. Qualified technicians in industry should train the students systematically. 3. The education of the technical high schools can not be relied on as the only training for the qualification examination. 4. It is necessary that technical high schools should give more importance to the culture of sentiments.