機(jī)械畢業(yè)設(shè)計(jì)外文翻譯-切割參數(shù)對(duì)芯片影響形成垂直切割論文-文庫吧
2025-06-09 16:56 本頁面
【正文】 構(gòu)、使用的刀具類型、機(jī)器穩(wěn)定性、熱生成和操作參數(shù)。[31]。切向力的數(shù)學(xué)模型的確定是由實(shí)驗(yàn)設(shè)計(jì)的方法。一個(gè)通用的這個(gè)模型的方程是:通過對(duì)數(shù)計(jì)算X的值轉(zhuǎn)換曲線的值選擇的因素(Vc、f)根據(jù)方程(2),bi系數(shù)的方程所有必需的計(jì)算后，一個(gè)簡單的切向力的數(shù)學(xué)模型,提出了在這里作為一個(gè)函數(shù)的切割速度方程7。驗(yàn)證的數(shù)學(xué)模型方程(7)如圖11所示。根據(jù)模型(7),參數(shù)方法圖(進(jìn)給速率/切削速度)(圖11b)可以繪制這將是一個(gè)象征車削加工參數(shù)的選擇困難。事實(shí)上,這個(gè)參數(shù)圖讓我們知道提要輪流的價(jià)值對(duì)于一個(gè)給定的切削速度和一個(gè)給定的切削力。通過修復(fù)兩個(gè)參數(shù)并提供曲線上的點(diǎn)選擇第三個(gè)。這個(gè)參數(shù)方法圖將其用于工作在鋼鐵制造商X160 CrMoV12收到或淬火條件。Mechanism of the chip formation Morphology of the chipMorphology of the chip As well known, all the materials do not show the same behaviour under the same cutting conditions. That is also true for the same material with various hardness that have undergone tothe different heat treatment [4]. In fact, Machining of X160CrMoV12 steel undergone to the heat treatment (quench) shows that the form and the morphology of chip are pletely different from that of obtained when the material has undergone to the annealing treatment [3,4,8] for the range of cutting conditions (. cutting speed, Vc varies from 50 to 250 m/min, and feed rate, f varies from to mm/rev) as shown in the Figures 3 and band formation can be easily observed depending on the machining conditions (Figure 3).The analysis of the chips formation shows that the contact of “toolchip” in case of increased loading and a heavily deformed zone are formed following the applied load.When the potential loading achieves a threshold value, a crack initiation appears easily in the zone where a considerable amount of chromium carbide is found in the matrix by forming an angle 0 with the direction of the cutting speed. This crack appears at the point of the tool leading a short relaxation. The crack initiation will produce the slip of the matter where the formation of a segment (slice). This phenomenon is repeated again by giving a new segment. And accordingly, the chip is formed in sawtooth type since the process is cyclic.In macroscale however, the chips obtained by hard turning, are relatively in different forms and they can change according to the cutting speed (Figure 4). These forms are developed helicoidally, tangled up either in detached form or in the form of continuous arc in the colour of blue and gray.Here typical chip morphology was identified to realize theeffect of cutting speed, feed rate, and depth of cut, etc. during the orthogonal cutting. However, more detailed research on the chip morphology in hard machining should be carried out to help reveal the segmentation chip formation mechanisms as well as encourage hard machining to be a practical expertise.Secondary carbidePrimary carbide Fig. 1. Microstructure as hardened state of AISI D2 amp。 chemical analysis obtained by EDS analysisa) b) c)Fig. 2. a) Specimen form, (b) orthogonal cutting, and c) the carbides in the matrix of the materials create grooves by wear on the toolFig. 3. a) Chip formation at Vc=100 m/min, f = mm/rev, ap=2mm。 b) Chip formation at Vc=250 m/min, f = mm/rev, ap=2mmFig. 4. Macrographic observation of the chip。 ap = 2 mm。 f = 。 (a) Vc = 50 m/min。 (b) Vc = 150 m/min。 (c) Vc = 250 m/mindifferent forms and they can change according to the cutting speed (Figure 4). These forms are developed helicoidally, tangled up either in detached form or in the form of continuous arc in the colour of blue and gray.Here typical chip morphology was identified to realize theInfluence of the feed on the form of chip The analysis of the chips shows that the feed rate by turn influences considerably the morphology of the chips. Certainly, the machining of steel “X160 Cr MoV12” hardened (62 HRC) with small feed rates (f = mm/rev) allows obtaining a continuous chip, this chip is due to a quasistationary plastic deformations in the zones of shearing (Figure 5).It should be noted that, with the in
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