| The acoustic emission is a phenomenon releasing elasticity energy in manner of wave with material or structural deformation or fracture by external force. Acoustic emission technique is a new advanced technology inspecting without damage, has been widely used in nondestructive testing equipment and online monitoring, As each material has different emission characteristics and each environment have different effects on the acoustic emission signals, AE technology needs to be study more in-depth to be used in wide area. In this paper, a large number scientific literature data inside nation and outside be referred, and acoustic emission technology applied in drawing. The headstream which the acoustic emission signals brought in the drawing has two genera, plasticity deformation and friction. As the friction in the process of the forming deformation with excellent lubricate may be ignored, it is considered that the source of the acoustic emission signals be from plasticity deformation mostly. The acoustic emission signals be composed of a series of telecom signal, the acoustic emission signal is more complex as sheet forming technics is complex and multiplex and as the acoustic emission signal is transient state and randomicity, so studying in-depth and meticulously is more need.In the paper the process of the drawing was detected and inspected by the acoustic emission, the acoustic emission signal collected under different conditions was studied and different factors fecting the acoustic emission signal was studied. The acoustic emission signal in the process of the drawing was collected and detected ,the diameter length, the speed of drawing and lubricating condition acting as independent variables, the amplitude, ringing counts, energy parameters acting as dependent variables, regression analysis was carried through.The drawing experiment is composed of 3 groups, first group is separately lubricating with sulfonated oil, with film containing sulfonated oil, without any lubricant, the diameter of test specimen is all 80 mm. the diameter of test specimen in the second group is separately 80 mm.90mmand100mm, the way of lubrication is same,the intention is to study that the diameter of test specimen have or have not the effect on acoustic emission. The test specimen of diameter 80 mm in third group is drawn with different drawing speed to study that the drawing speed have or have not the effect on acoustic emission. The results show that in the process of drawing experiment, it is seen from the testinf of goodness of fit that the changes of independent variable the diameter, the lubrication condition and the speed can always explain the changes of dependent variable amplitude, ring count and energy, moreover it can be known from tha model variance test that the relation between the diameter, the lubrication condition ,the speed and amplitude, ring count,energy is evidently linear. The conclusion is gotten by regress model as follow:(1) Drawing in the lubricating drop has more deep impact on the acoustic emission signals than the non-lubricated,in the lubricating,acoustic emission amplitude signal, ringing signal count, signal energy is decreased quickly than the non-Lubricated.(2)In the drawing process, the change of diameter, lubrication and drawing speed has a influence on the acoustic emission signal, the amplitude, the ring count and the energy of acoustic emission signal increases along with the increase of the diameter of workpiece drawn.(3)The change of drawing speed have a effect on acoustic emission, the acoustic emission signal rise with the increases of drawing speed. |
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