外文翻譯---金屬切削加工基礎(chǔ)知識節(jié)選

1、<p>　　金屬切削加工基礎(chǔ)知識節(jié)選</p><p>　　1 機械加工工藝系統(tǒng) </p><p>　　從機械制造的整個過程來看，機器的最基本組成單元為零件，也就是首先要制造出合格的零件，然后組裝成部件，再由零、部件裝配成機器，因此，制造出符合要求的各種零件是機械加工的主要目的，而機械加工中絕大部分材料是金屬材料，故機械加工主要是對各種金屬進行切削加工。</p>&l

2、t;p>　　零件的表面通常是幾種簡單表面如平面、圓柱面、圓錐面、球面、成形表面等的組合，而零件的表面是通過各種切削加工方法得到的，其中在金屬切削機床上利用工件和刀具彼此間協(xié)調(diào)的相對運動切除被加工零件多余的材料，獲得在形狀、尺寸和表面質(zhì)量都符合要求的這種加工方法稱為金屬切削加工。</p><p>　　金屬切削加工常作為零件的最終加工方法，它需要用金屬切削刀具直接對零件進行加工，它們之間要有確定的相對運動和承受

3、很大的切削力，通常需在金屬切削機床上進行加工，零件和刀具需通過機床夾具和刀架與機床進行可靠的聯(lián)接，帶動它們做相對的運動，實現(xiàn)切削加工，這種由金屬切削機床、刀具、夾具和工件構(gòu)成的機械加工封閉系統(tǒng)稱為機械加工工藝系統(tǒng)，其中金屬切削機床是加工機械零件的工作機械，起支承和提供動力作用；刀具起直接對零件進行切削加工作用；機床夾具用來對零件定位和夾緊，使之有正確的加工位置。本章就圍繞機械加工工藝系統(tǒng)四個組成部分進行分析，闡述機械零件加工的整個過程。

4、</p><p>　　2 切削運動與切削用量 </p><p><b>　　2.1 切削運動</b></p><p>　　金屬切削加工時，工件是機械加工過程中被加工對象的總稱，任何一個工件都是經(jīng)過由毛坯加工到成品的過程，在這個過程中，要使刀具對工件進行切削加工形成各種表面，必須使刀具與工件間產(chǎn)生相對運動，這種在金屬切削加工中必須的相對運動稱為切

5、削運動。以車床加工外圓柱面為例，圖2-1表示出了車削運動、切削層及工件上形成的表面。</p><p>　　圖2-1 車削運動、切削層及工件上形成的表面</p><p>　　切削運動可分為主運動和進給運動兩種。</p><p><b>　?。?）主運動</b></p><p>　　主運動是切除工件上多余金屬層，形成工件新表

6、面所必需的運動，它是切削加工中最基本、最主要的運動，通常它的速度最高、消耗的機床功率最多，如車削加工、鏜削加工時是工件的回轉(zhuǎn)運動，銑削加工和鉆削加工是刀具的回轉(zhuǎn)運動，刨削加工是刨刀的直線運動。</p><p><b>　　（2）進給運動</b></p><p>　　進給運動是把被切削金屬層間斷或連續(xù)投入切削的一種運動，與主運動相配合即可不斷地切除金屬層</p&g

7、t;<p>　　，獲得所需的表面。進給運動的特點是速度小，消耗功率少，可由一個或多個運動組成。圖2-1所示外圓車削中沿工件軸向的縱向進給運動是連續(xù)的，沿工件徑向的橫向進給運動，它是間斷的。 </p><p><b>　　(3)切削層</b></p><p>　　切削層是指切削時刀具切削工件一個單行程所切除的工件材料層。圖2-1所示，工件旋轉(zhuǎn)一周回到原來的

8、平面時，由于刀具縱向進給運動是連續(xù)的，刀具從位置Ⅰ移動到了位置Ⅱ，在兩個位置間形成的工件材料層（圖中ABCD區(qū)域）就是切削層。</p><p>　　(4)切削過程中工件上形成的表面</p><p>　　工件在切削過程中形成了三個表面：其中待加工表面是指工件上即將被切削掉的表面即圖中外圓表面1；過渡表面是工件上切削刃正在切削的表面，如圖中表面2；已加工表面是指工件上經(jīng)切削加工后形成的表面，如

9、圖中外圓表面3。</p><p><b>　　2.2 切削用量</b></p><p>　　刀具與工件之間有了相對運動才可以進行切削加工，用來衡量切削運動大小的參數(shù)稱為切削用量，切削速度、進給量和背吃刀量（切削深度）稱為切削用量的三要素。只有合理地確定切削用量才能順利地進行切削。</p><p><b>　　(1)切削速度 </

10、b></p><p>　　刀具切削刃上選定點相對于工件主運動的速度，單位為 或 。由于切削刃上各點的切削速度是不同的，計算時常用最大切削速度代表刀具的切削速度。外圓車刀車削外圓時的切削速度計算式為：</p><p><b>　?。?-2）</b></p><p>　　式中 —工件待加工表面的直徑（mm）， —工件的轉(zhuǎn)速（ ）。<

11、/p><p><b>　　(2)進給量 </b></p><p>　　刀具在進給運動方向上相對于工件的位移量稱進給量，不同的加工方法，由于所用刀具和切削運動形式不同，進給量的表述和度量方法也不同。進給量的單位是 （用于車削、鏜削等）或 行程（用于刨削、磨削等）。進給量表示進給運動的速度。進給運動速度還可以用進給速度 （單位是 ）或每齒進給量 （用于銑刀、鉸刀等多刃刀具，單

12、位是 齒）表示。一般</p><p><b>　　（2-3）</b></p><p>　　式中 —主運動的轉(zhuǎn)速（ ）， —刀具齒數(shù)。</p><p>　　(3)背吃刀量（切削深度） </p><p>　　在垂直于主運動方向和進給運動方向的工作平面內(nèi)測量的刀具切削刃與工件切削表面的接觸長度。對于外圓車削，背吃刀量為

13、工件上已加工表面和待加工表面間的垂直距離，單位 。即</p><p><b>　?。?-4）</b></p><p>　　式中 —工件待加工表面的直徑（ ）， —工件已加工表面的直徑（ ）</p><p>　　3 切削加工刀具的基本知識 </p><p>　　金屬切削過程中，直接完成切削工作的是刀具，而刀具能否勝任切

14、削工作，主要由刀具切削部分的合理幾何形狀與刀具材料的物理、機械性能決定。</p><p>　　3.1 刀具切削部分的結(jié)構(gòu)要素</p><p>　　切削刀具的種類很多，結(jié)構(gòu)也多種多樣。車刀、刨刀均屬單刃刀具，而鉆頭、銑刀等為多刃刀具，雖然它們形狀不同，但它們切削部分的結(jié)構(gòu)要素及其幾何形狀都具有許多共同的特征，因此正確認識與理解單刃刀具是認識與理解多刃刀具的基礎(chǔ)。</p><

15、;p>　　如圖3-1所示,車刀由刀體（夾持部分）與刀頭（切削部分）組成。刀體用來將車刀夾持在車床刀架上，起支承和傳力作用，刀頭擔(dān)負切削工作。車刀切削部分（又稱刀頭）由前刀面、主后刀面、副后刀面、主切削刃、副切削刃和刀尖所組成</p><p><b>　　圖3-1車刀的組成</b></p><p><b>　　其定義分別為：</b></

16、p><p>　?。?）前刀面（前面）刀具上與切屑接觸并相互作用的表面。</p><p>　?。?）主后刀面（主后面） 刀具上與工件過渡表面相對并相互作用的表面。</p><p>　?。?）副后刀面（副后面） 刀具上與工件已加工表面相對并相互作用的表面。</p><p>　?。?）主切削刃 前刀面與主后刀面的交線。它完成主要的切削工作。</p

17、><p>　?。?）副切削刃 前刀面與副后刀面的交線。它配合主切削刃完成切削工作，并最終形成已加工表面。</p><p>　　圖3-2刨刀、鉆頭、銑刀切削部分的形狀</p><p><b>　?。?）刀尖</b></p><p>　　主切削刃和副切削刃連接處的一段刀刃。它可以是小的直線段或圓弧。 </p>&l

18、t;p>　　由此可見，車刀主要由三個刀面、兩條切削刃和一個刀尖組成，其它各類刀具，如刨刀、鉆頭、銑刀等，都可看作是車刀的演變和組合。如圖3-2所示，刨刀切削部分的形狀與車刀相同（圖3-2a）；鉆頭可看作是兩把一正一反并在一起同時車削孔壁的車刀，因而有兩個主切削刃，兩個副切削刃，還增加了一個橫刃（圖3-2b）；銑刀可看作由多把車刀組合而成的復(fù)合刀具，其每一個刀齒相當(dāng)于一把車刀（圖3-2c）。</p><p>

19、　　3.2 刀具的幾何角度</p><p>　　（1）刀具角度參考坐標系</p><p>　　刀具角度是確定刀具切削部分幾何形狀的重要參數(shù)，要確定刀具的角度，必須先確定用于定義和規(guī)定刀具角度的各種基準坐標平面，組成各種參考坐標系，以外圓車刀為例在生產(chǎn)實踐中最常用的坐標系是正交平面參考坐標系，如圖3-3所示主要三個平面組成：</p><p>　?、倩?過切削刃選定點

20、，垂直于該點假定主運動方向的平面。用Pr表示。</p><p>　　②切削平面 過切削刃選定點，與切削刃相切，并垂直于刀具基面的平面。主切削平面用Ps表示，副切削平面用P’s表示。</p><p>　?、壅黄矫?過切削刃選定點同時垂直于刀具基面和切削平面的平面。用Po表示。</p><p>　　這三個平面兩兩相互垂直，稱為正交，故此坐標系叫做正交平面參考坐標系，在

21、圖中，過主切削刃選定點和過副切削刃選定點都可以建立正交平面參考坐標系，它們的基面同為平行刀具底面的平面。</p><p>　　圖3-3正交平面參考坐標系</p><p><b>　?。?）刀具角度</b></p><p>　　建立了正交平面參考坐標系，刀具的各個刀面與坐標系平面之間就產(chǎn)生了交角，這樣可以用它們來表示各個刀面的傾斜程度，從而改變刀

22、具的鋒利與強弱，設(shè)計、刃磨和測量刀具的幾何形狀，對外圓車刀來說，刀面主要有三個，每個刀面按一面兩角分析法需要兩個角度來確定其空間位置，因此總共需要六個角度來確定外圓車刀的幾何形狀，這六個角度稱為外圓車刀的獨立角度，如圖3-4所示：</p><p>　　圖3-4 正交平面參考坐標系的刀具角度</p><p>　　刀具角度是制造和刃磨刀具所需要的，并在刀具設(shè)計圖上予以標注的角度，以外圓車刀為例

23、，角度定義為：</p><p>　?、偾敖?在正交平面內(nèi)測量的前刀面與基面之間的夾角，前角表示前刀面的傾斜程度。前角越大刀具越鋒利，根據(jù)前刀面與基面相對位置的不同，又分別規(guī)定為正前角、零度前角和副前角。 </p><p>　?、谥骱蠼?在正交平面內(nèi)測量的主后刀面與切削平面之間的夾角。主后角表示主后刀面的傾斜程度，一般為正值。</p><p>　?、鄹焙蠼?在副切削刃

24、的正交平面內(nèi)測量的副后刀面與切削平面之間的夾角。副后角表示副后刀面的傾斜程度，一般為正值。</p><p>　?、苤髌?在基面內(nèi)測量的主切削刃在基面上的投影與進給運動方向的夾角。主偏角一般為正值。</p><p>　?、莞逼?在基面內(nèi)測量的副切削刃在基面上的投影與進給運動反方向的夾角。副偏角一般為正值。</p><p>　　⑥刃傾角 在切削平面內(nèi)測量的主切削刃與

25、基面之間的夾角。當(dāng)刃傾角為正時，刀尖的強度較低，鐵屑向刀架方向流出，適用于精加工類型刀具。</p><p>　　3.3 常用刀具材料</p><p>　?。?）刀具材料應(yīng)具有的性能 </p><p>　　金屬切削過程中，刀具切削部分在高溫下承受著很大切削力與劇烈摩擦，切削工作時，還伴隨著沖擊與振動，引起切削溫度的波動，因此，刀具切削部分材料應(yīng)具有良好的機械和物理化學(xué)

26、性能，主要是：</p><p>　?、俑哂捕?刀具材料的硬度必須高于被加工材料的硬度，一般刀具材料在室溫下都應(yīng)具有60HRC以上的硬度。</p><p>　　②高耐磨性 刀具與工件之間有很大的相對運動速度，產(chǎn)生的摩擦很大，需要很高的耐磨性，一般來說材料硬度越高耐磨性越好。</p><p>　?、圩銐虻膹姸扰c韌性 切削時刀具和工件間產(chǎn)生很大的切削力，同時又有較大的沖擊

27、力，故要求刀具材料要有足夠的強度與韌性來保證刀具不產(chǎn)生破壞。 </p><p>　?、芨叩哪蜔嵝?高耐熱性是指在高溫下仍能維持刀具切削性能的一種特性，通常用高溫硬度值來衡量，也可用刀具切削時允許的耐熱溫度值來衡量。它是影響刀具材料切削性能的重要指標。耐熱性越好的材料允許的切削速度越高。</p><p>　　刀具材料還需有較好的工藝性與經(jīng)濟性。工具鋼應(yīng)有較好的熱處理工藝性，淬火變形小，淬透層

28、深、脫碳層淺；高硬度材料需有可磨削加工性；需焊接的材料，宜有較好的導(dǎo)熱性與焊接工藝性。此外，在滿足以上性能要求時，宜盡可能滿足資源豐富、價格低廉的要求。</p><p>　　選擇刀具材料時，很難找到各方面的性能都是最佳的，因為材料性能之間有的是相互制約的，只能根據(jù)工藝需要保證主要需求的性能，如粗加工鍛件毛坯，需保持有較高的強度與韌性，而加工硬材料需有較高的硬度等。</p><p>　　Me

29、tal machining knowledge</p><p>　　1 Mechanical processing system</p><p>　　From the whole process of mechanical manufacturing, the most basic components of machine part, also is the first to produ

30、ce qualified parts, and then assembled into components, again from zero, parts assembly into machine, therefore, manufactured to meet the requirements of the various parts of processing machinery is main purpose, and in

31、the vast majority of material machining is a metal material, so the machining is mainly to a variety of metal cutting.</p><p>　　Parts of the surface is usually several simple surface such as plane, cylindric

32、al surface, conical surface, forming surface and spherical, combination, and the surface of the part is through a variety of machining method, in which the metal cutting machine tool with the workpiece and tool coordinat

33、ion relative movement of resection of part machining surplus materials, access to in shape, size and surface quality are compatible with the requirements of this process is called the metal cutting pro</p><p&g

34、t;　　Metal cutting processing, often as part of the final processing method, it needs to use metal cutting tools to process parts, between them to determine the relative motion and bear great cutting force, usually in the

35、 metal cutting machine tool for processing, parts and tools required by machine tool fixture and tool and machine tool for reliable connection they do the relative motion, drive, realize the cutting process, the metal cu

36、tting machine tool, cutting tool, fixture and workpiece machinin</p><p>　　2 Cutting motion and parameters</p><p>　　2.1 Cutting movement</p><p>　　Metal cutting processing, workpiece

37、machining process is processed object in general, any one of the workpiece are composed of rough processing to finished product process, in this process, to make the tool on the workpiece machining to form various surfac

38、es, must make the tool and workpiece relative motion is generated, this in metal cutting processing must be relative motion is known as the cutting movement. To lathe processing outer cylindrical surface as an example, F

39、igure 2-1 shows a turnin</p><p>　　Figure 2-1 turning movement, cutting layer and formed on the workpiece surface</p><p>　　Cutting motion can be divided into the main movement and feed movement o

40、f the two kind.</p><p>　?。?）Main movement</p><p>　　Main movement is the removal of the unnecessary metal layer, forming the new surface necessary for the movement, it is the most basic, cutting

41、the main motion, it is usually the highest speed, consumption of machine tool power most, such as turning, boring machining workpiece turning, milling and drilling processing cutter rotary motion, planing is planing line

42、ar motion.</p><p>　?。?）Feed motion</p><p>　　Feed movement is to be cutting metal layer intermittent or continuous input of cutting a movement, with the main movement coordination can becontinuou

43、sly removed metal layer，to obtain the desired surface. Feed motion is characterized by low speed, low power consumption, can be composed of one or more exercise. Figure 2-1 in excircle turning along the axial direction o

44、f the longitudinal feed motion is continuous, radially along the workpiece transverse feeding motion, it is intermittent.</p><p>　?。?）Layer cutting</p><p>　　Cutting layer refers to cutting cutti

45、ng workpiece to a single stroke the resection of the workpiece material layer. Shown in Figure 2-1, the workpiece rotates a circle back to the original level, because the tool longitudinal feed motion is continuous, the

46、cutting tool from the position I had moved to position II, in the two position of the formed workpiece material layer (Figure ABCD region ) is cutting layer.</p><p>　　（4）The cutting process is formed on the

47、workpiece surface</p><p>　　The workpiece in the cutting process in the formation of the three surfaces: one of the surfaces to be processed is refers to the workpiece to be cut away the surface figure extern

48、al circular surface 1; the transition surface is the workpiece cutting edges are cutting surface, as shown in the figure 2 surface; surface refers to the workpiece by the cutting process after the formation of the the su

49、rface of external circular surface, as shown in figure 3.</p><p>　　2.2 Cutting</p><p>　　Between the tool and the workpiece with relative movement can be cutting, used to measure the movement of

50、 cutting size parameter called the cutting parameters, cutting speed, feed rate and depth ( depth ) called the cutting elements of the three. It is only reasonable to determine the amount of cutting can be carried out sm

51、oothly cutting.</p><p>　　（1）Cutting speed</p><p>　　The cutting edge of selected points on the workpiece relative to the main movement speed, unit or. Because each point on the cutting edge of th

52、e cutting speed is different, when calculating the maximum cutting speed cutting tool used on behalf of the cutting speed. The outer circle lathe turning cutting speed calculation formula: </p><p><b>　

53、　( 2-2 )</b></p><p>　　In — the workpiece surface diameter ( mm ), —workpiece speed ().</p><p><b>　　(2) Feed</b></p><p>　　Cutting tool in the direction of feed on t

54、he workpiece relative to the displacement of said feed, different processing methods, the cutting tool and the cutting movement in different forms, the feed formulation and measurement methods are also different. Feed un

55、it( used for turning, boring )or Stroke ( used for planing, grinding etc.). The feed that feed movement speed. Feed velocity can also be used to feed speed( company) Or feed per tooth( used for milling cutter, reamer, cu

56、tter, unit is Toot</p><p><b>　?。?-3）</b></p><p>　　Type of—main motor speed（ ）, —the cutter teeth.</p><p>　　(3) Back cutting depth (depth of cut ) </p><p>　　

57、In the direction perpendicular to the direction of main movement and feed movement in the direction of the working plane measurement of workpiece and the cutting tool edge cutting surface contact length. For cylindrical

58、turning, back cutting depth for the workpiece on the machined surface and the vertical distance between the surface to be machined, the unit. That is</p><p><b>　　( 2-4 )</b></p><p>　

59、　In —the workpiece surface diameter ( ), — machined surface diameter ( )</p><p>　　3 Cutting tool basic knowledge</p><p>　　In the process of metal cutting, cutting work is done directly tool, and

60、 the cutting tool is fit for cutting work, mainly by cutting part of the tool geometry and cutting tool materials reasonable physical, mechanical properties.</p><p>　　3.1 Cutting part of the tool structural

61、elements</p><p>　　Cutting tool type are many, varied structure. Lathe tool, planer is a single-point cutting tool, and the drill bit, cutter, cutter, although they differ in shape, but they are cutting part

62、of the structural elements and geometry have many features in common, so a correct understanding and understanding a single-point cutting tool is the recognition and understanding of knife with foundation.</p><

63、;p>　　As shown in Figure 3-1, tool comprises a knife body ( clamping part) and the cutter head ( cutting ). The knife body is used to the tool clamp on lathe tool holder, supporting and force transmission effect, the c

64、utter head to cutting work. Tool cutting part ( also known as the cutter head ) by the rake face, the flank, minor flank, the main cutting edge, a secondary cutting edge and tip.</p><p>　　Figure 3-1tool.<

65、/p><p>　　Their definitions respectively:</p><p>　　(1) front ( front) tool and chip contact and the interaction of surface.</p><p>　　(2) the flank ( main behind the cutter and workpiece

66、 ) transition surface relative to and interacts with the surface of.</p><p>　　(3) the minor flank ( side behind) tool and machined surface relative to and interacts with the surface of.</p><p>　

67、　(4) the main cutting edge rake face and flank of the intersection of main. It completes the main cutting work.</p><p>　　(5) a secondary cutting edge rake face and flank of the line side. It is matched with

68、the main cutting edge finish cutting, and finally forming the machined surface.</p><p>　　Figure 3-2 cutter, drill bit, milling cutter cutting section shape</p><p>　　(6) the main cutting edge and

69、 the side cutting edges at the connection of a blade. It can be small line segment or arc.</p><p>　　Thus, turning tool is mainly composed of three blades, two cutting edges and a nose, and other types of too

70、ls, such as knives, drill bits, milling cutter, can be seen as the evolution and combination tool. As shown in Figure 3-2, planing cutting part of the tool shape and same ( Figure 3-2a ); the drill bit can be regarded as

71、 two positive and reverse turning hole wall and at the same time the tool, which has two main cutting edge, two side cutting edge, also adds a transverse blade (FIG. 3-2b );</p><p>　　3.2 Tool geometric angle

72、</p><p>　　(1)Tool angle reference coordinate system</p><p>　　The angle of cutting tool is to determine the cutting part of the tool geometry parameters, to determine the angle of cutting tool, m

73、ust determine for definitions and regulations angle of various reference plane, consisting of various reference coordinate system, outside round tool as an example in the production practice of the most commonly used coo

74、rdinates are orthogonal plane reference coordinate system, as in Figure 3-3 in three main planar composition:</p><p>　?、?surface cutting edge of selected points, perpendicular to the point of main movement d

75、irection of plane assumption. To express with Pr.</p><p>　?、?the cutting plane cutting edge of selected points, and cutting edge tangential and perpendicular to the cutting tool, the flat base surface. The m

76、ain cutting plane is indicated by Ps, side cutting plane with P ' s.</p><p>　?、?orthogonal plane cutting edge selected point and perpendicular to the base surface and the cutting plane of the plane cutte

77、r. To express with Po.</p><p>　　The three planar two two mutually perpendicular, called orthogonal coordinate system, so called orthogonal plane reference frame, in the picture, the main cutting edge and the

78、 side cutting edges of selected points selected point can be established in the orthogonal plane reference coordinate system, their base with the bottom surface of the flat surface parallel tool.</p><p><

79、b>　　分享到 </b></p><p><b>　　翻譯結(jié)果重試</b></p><p>　　抱歉，系統(tǒng)響應(yīng)超時，請稍后再試</p><p>　　支持中英、中日在線互譯</p><p>　　支持網(wǎng)頁翻譯，在輸入框輸入網(wǎng)頁地址即可</p><p>　　提供一鍵清空、復(fù)制功能、支持

80、雙語對照查看，使您體驗更加流暢</p><p>　　Figure3-3 orthogonal plane reference coordinate system</p><p>　　(2)Angles of cutter</p><p>　　Establishment of plane coordinate system, cutter knife surface

81、and each coordinate plane arose between angle, so that they can be used to express the degree of tilt of each knife, thereby changing the sharp edges of the cutter and the strength, design, grinding and measuring tool ge

82、ometry, the cylindrical turning tool, knife surface are three main one, each blade according to the side two analysis requires two angles to determine the spatial position, therefore requires a total of six angles to <

83、;/p><p>　　Figure3-4The orthogonal plane of the reference coordinate system of cutting tool angle</p><p>　　The angle of cutting tool manufacturing and grinding tool is needed, and the cutter design

84、drawing shall be stated angle, outside round tool as an example, the angle is defined:</p><p>　?、?anterior horn in the orthogonal plane measurement of the rake face and the angle between the front surface, a

85、ngle of rake face inclined degree. Higher the rake angle cutter sharper rake face and the base surface, according to the relative positions of the different, respectively defined as positive rake angle, zero rake angle a

86、nd side rake angle.</p><p>　?、?the angle in the orthogonal plane measurement of the flank and the angle between the cutting plane. After the main main flank angle of tilt degree, generally positive.</p>

87、;<p>　?、?side angle in the side cutting edges orthogonal plane measuring side flank face and the angle between the cutting plane. Back clearance angle said side flank inclination degree, generally positive.</p&

88、gt;<p>　?、?the main angle in the inner base surface measurement of the main cutting edge on the base with the direction of feed angle projection. The main general positive angle.</p><p>　?、?on the sur

89、face side angle measurement in the secondary cutting edge on the surface projection and the feed motion in the opposite direction angle. General positive side angle.</p><p>　?、?in a cutting plane cutting edg

90、e inclination measurement in the main cutting edge and base of the angle between the. When the blade is positive, the strength of the tool tip is low, iron filings to knife direction outflow, applicable to finish type cu

91、tter.</p><p>　　3.3 Commonly used tool materials</p><p>　　(1)Tool material should have the properties of</p><p>　　In the process of metal cutting, cutting part of the tool at a high

92、temperature under a lot of cutting force and cutting of intense friction, when working, also accompanied by shock and vibration caused by cutting, temperature fluctuations, therefore, cutting part of the tool materials s

93、hould have good mechanical and physical and chemical properties, mainly:</p><p>　　① high hardness hardness must be higher than the material hardness, general cutting tool materials at room temperature shall

94、be above 60HRC hardness.</p><p>　?、?high wear resistance between the tool and the workpiece has a lot of relative motion velocity, friction, require high wear resistance material, generally the higher hardne

95、ss wear resistance.</p><p>　?、?sufficient strength and toughness of cutting tool and workpiece to produce great cutting force, simultaneously also has the big impact force, the cutting tool material should h

96、ave enough strength and toughness to ensure that the tool does not generate damage.</p><p>　?、?high heat resistance and high heat resistance is at a high temperature can still maintain the cutting performanc

97、e of a character, usually with high temperature hardness values measured, can also be used while the tool is cutting allows the heat resisting temperature values measured. It is the important index of cutting tool materi

98、al. Heat resistance and better material allows the cutting speed is higher.</p><p>　　Tool material should also have better technological and economic. Tool steel should have good heat treatment, quenching de

99、formation, hardening layer depth, decarburized layer shallow; high hardness materials need grinding processing; welding material, should have better thermal conductivity and welding technology. In addition, in satisfies

100、the performance requirement, should as far as possible to meet the requirements of rich resources, low price.</p><p>　　Selection of cutting tool materials, it is difficult to find all aspects of performance

101、are the best, because the material properties between some restrict each other, can according to the needs of technology to ensure that the main performance requirements, such as rough rough forging, required to maintain