[雙語(yǔ)翻譯]機(jī)械加工外文翻譯--氣動(dòng)快速停止裝置在切削區(qū)振動(dòng)車(chē)削的表征

1、3900 英文單詞， 英文單詞，2 萬(wàn)英文字符，中文 萬(wàn)英文字符，中文 6400 字文獻(xiàn)出處： 文獻(xiàn)出處：Amini S , Lotfi M , Paktinat H , et al. Characterization of vibratory turning in cutting zone using a pneumatic quick-stop device[J]. Engineering Science and Technolog

2、y, an International Journal, 2017, 20(2):403-410.Characterization of vibratory turning in cutting zone using a pneumatic quick-stop deviceSaeid Amini, Mohammad Lotfi, Hossein Paktinat, Mohsen KazemiyounAbstract Shear an

3、gle and sticking length are two crucial parameters in mechanics of metal cutting. These two parameters directly influence machinability factors such as cutting forces. Thus, shear angle and sticking length were investiga

4、ted in vibratory turning process by using a pneumatic quick-stop device which was designed and fabricated, in this study. After preparation of ultrasonic assisted turning set-up, experimental tests have been carried out

5、on two types of steel: AISI-1060 and AISI 304. Accordingly, the process of chip formation in each particular cutting test was quickly stopped when deformed chip was still in contact with workpiece. As a result, it was re

6、vealed that added linear vibration leads the turning operation to be improved by increase of shear angle and decrease of sticking length. Moreover, the effect of ultrasonic vibration on cutting force and chip micro-hardn

7、ess is evaluated.Keywords: Shear angle; Sticking length; Ultrasonic; Vibratory turning; Quick-stop; Micro-hardness1. IntroductionChip removal process using a cutting tool is entitled machining operation. In other words,

8、unwanted materials are cut from a raw material and the desired dimensions are achieved. One special state of machining is orthogonal cutting process where there are two most important deformation zones named primary and

9、secondary shear zones [1–3], as shown in Fig. 1.In the primary zone (ABCO), by advancing of cutting edge into the workpiece, chip is formed under a shear angle (u). The angle at which the chip is separated from the workp

10、iece is called shear angle which determines many essential aspects of the cutting mechanics such as the magnitude of the cutting force, the specific cutting energy and the finished surface. Larger shear angles produce sm

11、aller cutting force, further continuous and thin chip and better surface quality [4–6]. In the secondary zone (OCD), deformed chip moves on the tool rake surface until chip separation happens [4]. According to the experi

12、mental and analytical studies carried out by [7–9] and photo-elastic analysis performed by [10,11], it is proved that there are two zones in tool-chip contact region (secondary zone), sticking and sliding, respectively.I

13、n sticking region, chip is subjected to high pressure- temperature contact (atomic contact) close to the tool tip. As usual, contact shear stress is assumed to have uniform distribution and maximum value, in this region

14、[7,8]. High pressure near the head of cutting edge causes real and apparent contact areas to be approximately equal for some distance along the tool rake face. In this zone, the friction force is equal to the shear stren

15、gth of chip. In sliding region, the remaining contact area, as referred its name, chip has a relative motion on tool rake face, thereby pressure is dropped down leading the friction to the coulomb frictional condition [1

16、,7,8,11,12]. Since the contact condition between tool and chip is an important issue, study of this region is being one of the most important interests of researchers. Bahi et al. [13] proposed a hybrid analytical–numeri

17、cal model to study the tool-chip interface. They also discussed the effect of cutting From the point of mechanics of metal cutting and previous studies, whatever the sticking length to be smaller and shear angle to be la

18、rger, performance of cutting process improves. On the other hand, investigation of these two parameters specially sticking length has rarely been carried out under ultrasonic vibrations. Therefore, in this study, an atte

19、mpt is made to analyze these two parameters in UAT. Accordingly, a quick-stop device (QSD) was designed and fabricated and experimental tests were accomplished on two types of steel. In the following, shear angle and sti

20、cking length coupled with cutting forces were measured in UAT and compared with those obtained in CT. Moreover, the influence of turning methods on micro-hardness of deformed chip is studied.2. Materials and methods2.1.

21、Design and fabrication of vibratory toolShear angle and sticking length can be measured in experiment if the cutting tool is quickly driven out from the engagement where deformed chip is still in contact with workpiece.

22、This operation is commonly carried out by the help of a quick-stop device. However, a special feature needs to be designed and fabricated in a way that it takes vibratory turning tool away from the machining region.To de

23、sign a vibratory tool consists of an ultrasonic transducer, booster, horn and cutting tool, horn was modeled and modal analysis was carried out in ABAQUS software. This analysis is necessary because the resonance frequen

24、cy of horn part should be compatible with the one produces by transducer and booster. The resonance frequency of transducer used in this study was 20 ± 0.5 kHz. Finally, the designed horn was made of stainless st

25、eel (Table 1), in which its resonance frequency was 20450 Hz (Fig. 2). Furthermore, a scheme of assembled vibratory tool is displayed in Fig. 3.Table 1.Mechanical properties of horn partMaterial Density (kg/m3) Elasticit

26、y module (GPa) Poisson’s ratioAISI 304 8000 193 0.29Fig. 2. Modal analysis and the designed horn2.2. Design and fabrication of QSDAs shown in Fig. 4, a special pneumatic quick-stop device was designed in accordance with

27、weight and size of vibratory tool. It consists of following main parts: fixtures; pneumatic jack and pin; L-shape plane; bush; joints; guides; stop screw; and main body. The way of their functions are separately describe