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In the field of sheet metals forming, the press forming is executed as important method for mass production processing. It is reported that the plastic formability of Mg-alloy improves in the warm working. The warm deep drawing tests was carried out by using the 2 kinds of punch diameter, 30 mm and 50 mm. This paper describes about the optimum deep drawing conditions with forming temperature and lubricant in the magnesium AZ31B alloy and the flame retardant magnesium alloy AMX602. These Mg alloys are difficult to mold at room temperature. However, in forming temperature at 180℃-200℃, Limiting Drawing Ratio (LDR) of AZ31B became 2.65. The optimum forming temperature condition of AZ31B is 180℃-200℃. The value of LDR decreases at 200℃ or more. LDR of retardant magnesium alloy AMX602 is also 2.65 at the temperature at 300℃-320℃. The optimum temperature conditions of retardant magnesium alloy AMX602 is assumed to be 300℃ or more. After molding, the thickness decreases from the punch shoulder to the part around the sidewall. The magnesium alloys in thickness change is similar to the common deep drawing with the other materials. In AZ31B alloy and AMX602 alloy, the failure pattern is often occurred at sidewall area and punch-shoulder area respectively.

The deep drawability of flame-retardant Amca602 magnesium alloy sheets (aluminum, 6.5%; zinc, 0.08%, manganese, 0.32%; calcium, 2.1%) was investigated. Firstly, fundamental mechanical properties were obtained by performing uniaxial tension tests in the range of temperatures of 160-320°c. The tensile velocity was 0.5, 5 or 50 mm/min. Next, in deep-drawing tests, the temperature and punch velocity were changed, and a punch with a diameter of 10 mm was used. The experimental temperature was changed in the range from 240 to 340°c in increments of 20°c, and the punch velocity was 0.1, 0.5, 1.0 or 1.5 mm/s. Deep drawability improved as the temperature increased. The optimum deepdrawing temperature was found to be 320°c. A numerical simulation of deep drawing was conducted by finite element method for examining stress and strain distribution around breaking location. The experimental results and numerical simulation results were in relatively good agreement. A maximum deep-drawing depth was also obtained in the experiments and simulation.

In this paper, attempts were made to establish a system to monitor the behavior of small-diameter milling-cutters during high-speed milling, by using of visualization based on high-speed CCD camera. Experiments were designed to investigate the characterization of the cutter behavior during the high-speed milling. The image of cutter failure was caught successfully, and the characteristic image is found to be distinct before the breaking of the cutter. This can be used as an index to predict in process the cutter failure, and so the cutter breaking will be avoidable during high-speed milling. Experimental System and Image ProcessingExperimental System and Condition. The system includes machining center, CCD camera, laser sensor, trigger generator, light source and personnel computer, as shown in Fig. 1, where Fig. 1a shows the picture and Fig. 1b the signal flow.