※一部利用できない機能があります
| 1.
論文 |
論文
|
千徳, 英介 ; 上田, 隆司 ; 山田, 啓司 ; 細川, 晃
概要:
Laser forming of a sheet metal is the bending process caused by the thermal stresses which is produced in the sheet by l
…
aser irradiation. Therefore, the temperature distribution in the sheet irradiated with laser beam is one of important factors to determine the bending angle of the sheet. In this study, the influence of temperature distribution and the experimental conditions like the diameter of laser beam and the thickness of a sheet on the bending angle is investigated experimentally. The temperatures of a surface irradiated with CO2 laser and its opposite surface are measured using an infrared radiation pyrometer with an optical fiber. As a result, the bending angle is directly proportional to the temperature Ts at the sheet surface irradiated with laser beam and the beam diameter D, and inversely proportional to the thickness h of the sheet. A parameter indicated by D1.41Ts1.5/h1.7 has high correlation with the all bending angles obtained under various experimental conditions. 様々な加工条件で板材のフォーミング加工を行い, 同時にレーザ照射部表面および裏面温度を測定し, 加工条件と照射温度の変形角への影響を調べた. その結果, 変形角はレーザビーム径の1.4乗に比例し, 照射温度の1.5乗に比例し, 加工物の板厚の1.7乗に反比例しており, これらの結果より導出した式は定性的に加工条件の変形角への影響を良く表している.
続きを見る
|
||||
| 2.
論文 |
論文
|
田中, 隆太郎 ; 山根, 八洲男 ; 岡田, 将人 ; 細川, 晃 ; 上田, 隆司
概要:
This paper deals with the machinability of BN added Steels in end milling. The cutting tests were carried out by end mil
…
ling carbon steel JIS S45C, S55C and these BN added steels with carbide tool and TiAlN coated carbide tool. Tool wear, cutting temperature, and, surface roughness were measured and discussed. In end milling BN added steel with square end mill, the progress rate of flank wear width was decreased and fracture at corner was suppressed in comparison with that in machining standard steel. In case of ball end mill, flank wear in end milling BN added steels were smaller in comparison with standard steel. In case of S45C, boundary wear was observed, however it was not observed in end milling BN added steel. BN added showed almost the same surface roughness as standard steel. The temperature of flank wear part in turning work based S55C were 50 °C higher in comparison with S45C base work. The temperature of throw away end mill was higher 100°C in comparison with solid square end mill. There were not significant difference between the temperature in end milling standard steel and BN added steels.
続きを見る
|
||||
| 3.
論文 |
論文
|
上田, 隆司 ; 鳥居, 明人 ; 山田, 啓司
概要:
In surface grinding of steel, the temperature in the surface layer of the workpiece and the temperature of cutting grains on wheel surface are measured by means of a new method, in which an optical fiber accepts the infrared flux
…
radiated from the object and transmits it to an infrared detector InAs cell. This I.R.P. is suitable for measuring the temperature of a very small object whose temperature changes rapidly. The influence of the physical properties of workpiece and grinding conditions on the grinding temperature and the thermal partition coefficient are investigated. A carbon steel, a stainless steel and a cast iron are used as work materials. The thermal partition coefficients obtained by experimental results are compared with those obtained theoretically.
続きを見る
|
||||
| 4.
論文 |
論文
|
上田, 隆司 ; 山田, 啓司 ; 及川, 志郎 ; 細川, 晃
概要:
Laser forming is the thermal process to deform a metal plate using the thermal stress produced by the rapid heating with the laser. In this study, the influence of irradiating conditions of CO2 laser on the bending angle of the
…
workpiece is investigated. The temperature at the back surface of the workpiece irradiated with CO2 laser is measured using a two-color pyrometer with an optical fiber. The temperature distribution in the workpiece is calculated using the FEM thermal analysis. Simple bending experiments with one-way laser scanning are carried out. Stainless steel SUS304 of various thickness is used as work material. The results obtained are as follows. The bending angle is proportional to the temperature of the workpiece irradiated. The temperature of workpiece increases with the increase of laser power, the decrease of feed rate of the laser beam and the decrease of plate thickness. After all, the bending angle becomes larger with the increase of laser power, the decrease of the feed rate and the decrease of the thickness of the plate. The temperature of the workpiece can be used as a signal to control the deformation of the workpiece.
続きを見る
|
||||
| 5.
論文 |
論文
|
上田, 隆司 ; 佐藤, 昌彦 ; 杉田, 忠彰
概要:
Temperature of interface between a cutting tool and a workpiece is measured using two-color pyrometer with a fused fiber
…
coupler. A conical tool is used as the cutting tool which is made of translucent alumina sintered under HIP, and 0.55% carbon steel is used as a workpiece. The infrared rays radiated from the interface and transmitted through the conical tool are accepted by a fused fiber coupler and led to two infrared detectors of different spectral sensitivity. Temperature is obtained by calculating the ratio of the output voltage from these two detectors. The results obtained are as follows. The temperature increases very rapidly and reaches 1000°C at about 40 μs after the beginning of cutting. The rate of increase of temperature is very great : about 108 °C/s at the cutting speed of 1 500 m/min. The temperature increases with the increase of cutting speed, but at a speed faster than 1000 m/min its influence is small. The temperature shows a tendency to saturate about 1300-1400°C as the cutting speed increases.
続きを見る
|
||||
| 6.
論文 |
論文
|
上田, 隆司 ; 入山, 孝宏 ; 杉田, 忠彰
概要:
A new type of Infrared Radiation Pyrometer using a fused fiber coupler is made, and its characteristics are investigated theoretically and experimentally. This pyrometer can be applied to measure the flush temperature of a small area on
…
ceramics (PSZ) when it is irradiated with CO2 laser. In this pyrometer, the infrared rays radiated from the object are accepted by an optical fiber, and divided into two parts and transmitted to the two types of infrared detectors by a fused fiber coupler. The temperature is obtained by calculating the ratio of the output voltages from these two detectors. The characteristics of this pyrometer are as follows. It is possible to measure the temperature with controlling the disturbance of the emissivity. When the object has a surface of uniform temperature, the measuring temperature does not depend on the size of the object. In the case when the object has the distribution in temperature, it is possible to estimate the maximum temperature correctly from the experimental results.
続きを見る
|
||||
| 7.
論文 |
論文
|
Al Huda, Mahfudz ; 山田, 啓司 ; 上田, 隆司
概要:
The temperature of the flank side of the cutting tool edge that has large affect on machined surface integrity is measur
…
ed using two-color pyrometer with a fused fiber coupler. The infrared rays radiated from the cutting tool edge are accepted by an optical fiber, and separated to two optical fibers at the fused fiber coupler. Each fiber leads the infrared ray, respectively, to two infrared detectors with different characteristic of spectral sensitivity. Temperature is obtained by calculating the ratio of the output voltage from these two detectors. A CBN tool (CBN content : 60 volume percent, density : 3000 kg/mm2) is used as the cutting tool. Annealed steel (S45C), bearing steel (SUJ2), and quenched steel (S55C) are used as the cutting materials to investigate their affect on the tool edge temperature. The results obtained are as follows : (1) The technique developed is suitable for measuring the temperature of the flank side of the cutting tool edge. (2) The temperature of the cutting tool edge is highly effected by cutting speed. (3) The temperature increases slightly with the increase of depth of cut and feed rate. (4) On the cutting of quenched steel which has the largest hardness among these three materials, the temperature is about 50°C higher than that on the bearing steel cutting, and the temperature of the annealed steel cutting is the lowest.
続きを見る
|
||||
| 8.
論文 |
論文
|
佐藤, 昌彦 ; 上田, 隆司 ; 西田, 昌弘
概要:
Tool face temperature of single crystal diamond in high precision orthogonal cutting of aluminum and copper is measured
…
using two-color pyrometer with an optical fiber. The infrared rays radiated from the chip-tool interface and transmitted through the diamond tool are accepted by an optical fiber and led to two-color detectors of different spectral sensitivity. Temperature distribution on the tool face is analyzed by employing finite element method and calculated results are applied to the estimation of the maximum temperature on the tool face. The results obtained are as follows; (1) The technique developed is suitable for measuring the tool face temperature in single crystal diamond cutting. (2) Output wave of temperature was clearly recorded. The tool face temperature measured is approximately 190°C for Al and approximately 220°C for Cu when cutting speed was about 620m/min. (3) The temperature increases with the increase of cutting speed. (4) The temperature on the tool face measured is in good agreement with that calculated.
続きを見る
|
||||
| 9.
論文 |
論文
|
細川, 晃 ; 小田, 健作 ; 山田, 啓司 ; 上田, 隆司
概要:
The temperature of cutting tool in high speed endmilling is measured using a two-color pyrometer with an optical fiber.
…
This pyrometer has a flat response for the square-wave signal up to approximately 400kHz, which is enough speed to measure the temperature of an endmilling cutter passing at a cutting speed of 628m/min. The influence of cutting speed v and feed per tooth f on the cutting temperature at the flank face of the cemented carbide insert is investigated. The heating and cooling characteristics of the cutting tool during an intermittent cutting cycle are also examined. In dry cutting of carbon steel, the cutting tool temperature θα rises rapidly with the increase of cutting speed and θα reaches approximately 770°C at v=628m/min. The feed per tooth, however, has less effect on cutting tool temperature. The temperature change during an intermittent cutting process is about 150°C when v=471.2m/min and f=0.047mm/tooth. The temperature distribution along the contact edge between a tool and workpiece is almost uniform although those at tool tip and boundary region are somewhat higher.
続きを見る
|
||||
| 10.
論文 |
論文
|
上田, 隆司 ; 佐藤, 昌彦 ; 金田, 泰幸 ; 杉田, 忠彰
概要:
A temperature at the tip of a conical cutting tool is measured immediately after micro chip forming using an infrared ra
…
diation pyrometer with an optical fiber. The fundamental structure of this pyrometer is that the infrared flux radiated from the tip of the conical cutting tool after cutting is accepted and transmitted to an infrared detector InSb by an optical fiber. The measurement accurancy when applying the pyrometer to the experiment is investigated theoretically. The temperature at the tip of the conical tool at various cooling times after cutting is measured using this pyrometer. A carbon steel and a tungsten are used as workpieces. A cooling characteristic of the tool is analyzed by heat transfer theory. Applying the theoretical results to the experimental results, the temperature of the tip of the conical tool just after cutting is estimated to be 1500°C for carbon steel and 2400°C for tungsten; 1500°C is almost equal to the melting point of carbon steel.
続きを見る
|
