金屬的熱處理外文翻譯

1、<p><b>　　外文資料翻譯</b></p><p>　　Heat Treatment of Metal</p><p>　　The generally accepted definition for heat treating metals and metal alloys is “heating and cooling a solid metal o

2、r alloy in a way so as to obtain specific conditions and I or properties.”Heating for the sole purpose of hot working(as in forging operations) is excluded from this definition．Likewise，the types of heat treatment that a

3、re sometimes used for products such as glass or plastics are also excluded from coverage by this definition．Transformation Curves. </p><p>　　The basis for heat treatment is the time-temperature-transformatio

4、n curves or TTT curveswhere，in a single diagram all the three parameters are plotted．Because of the shape of thecurves，they are also sometimes called C-curves or S-curves．</p><p>　　Material forming proces

5、ses</p><p>　　In this section，a short description of the process examples will be given. But assembly and joining processes are not described here.</p><p><b>　　Forging</b></p>

6、<p>　　Forging can be characterized as: mass conserving, solid state of work material (metal), and mechanical primary basic process-plastic deformation. A wide variety of forging processes are used, and Fig.9.1(a) sh

7、ows the most common of these: drop forging. The metal is heated to asuitable working temperature and placed in the lower die cavity. The upper die is then lowered so that the metal is forced to fill the cavity. [1]Excess

8、 material is squeezed out between the die face sat the periphery as fla</p><p>　　Normally, forged components require some subsequent machining, since the tolerances and surfaces obtainable are not usually sa

9、tisfactory for a finished product. Forging machines include drop hammers and forging presses with mechanical or hydraulic drives. These machines involve simple translatory motions.</p><p><b>　　金屬的熱處理&l

10、t;/b></p><p>　　普遍認(rèn)同對(duì)金屬及合金熱處理的定義是，以一定的方式加熱或冷卻固態(tài)金屬或合金，以達(dá)到一定的條件和/或獲得某些性能。以熱加工(如鍛造)為目的的加熱，不在此定義之列。同樣地，有時(shí)用于生產(chǎn)諸如玻璃或塑料制品的熱處理也不屬于該定義的范疇。</p><p>　　相變曲線(xiàn)熱處理的基礎(chǔ)分別是時(shí)間—溫度相變曲線(xiàn)，即TTT 曲線(xiàn)，3 個(gè)參數(shù)都繪制在一個(gè)圖中。根據(jù)曲線(xiàn)的形狀特

11、點(diǎn)，分別稱(chēng)為C 曲線(xiàn)或S 曲線(xiàn)。</p><p>　　為了繪制 TTT 曲線(xiàn)，將特定的鋼置于給定溫度下，以預(yù)先確定的時(shí)間間隔檢查其結(jié)構(gòu)，記錄發(fā)生相變的量。我們知道共析鋼(C80)在平衡條件下，在723℃以上時(shí)全為奧氏體，而低于此溫度，則為珠光體。為了形成珠光體，碳原子將產(chǎn)生擴(kuò)散形成滲碳體。擴(kuò)散是一種漸進(jìn)過(guò)程，需要足夠的時(shí)間完成奧氏體向珠光體的轉(zhuǎn)變。對(duì)于不同的樣品，可以記錄下在任一溫度時(shí)產(chǎn)生相變的量。然后把這些點(diǎn)繪

12、制在一條以時(shí)間和溫度為坐標(biāo)軸的曲線(xiàn)上。通過(guò)這些點(diǎn)就可以得到共析鋼的相變曲線(xiàn)。左邊的曲線(xiàn)表示任一給定溫度下奧氏體</p><p><b>　　材料成型工藝方法</b></p><p>　　鍛造：鍛造是對(duì)固態(tài)金屬材料進(jìn)行初步機(jī)械加工，是產(chǎn)生塑性成形的質(zhì)量守恒的一種基本工藝方法。鍛造有很多類(lèi)型，最普通的鍛造為金屬加熱到適合加工的溫度，并放進(jìn)下型腔里。上型腔與下型腔合攏，迫使

13、金屬充滿(mǎn)型腔。多余的材料被從型腔接縫處擠出，并將被后續(xù)的清理型腔接縫工藝清除。當(dāng)提到鍛造術(shù)語(yǔ)時(shí)，通常意味熱鍛。冷鍛有幾種專(zhuān)門(mén)的名稱(chēng)。鍛造工藝中損失的材料通常相當(dāng)少。通常，由于公差和表面粗糙度通常不能滿(mǎn)足最終產(chǎn)品的需要，因此對(duì)鍛造的零件要進(jìn)行一些后續(xù)加工。鍛造機(jī)械包括落錘和機(jī)械或水力驅(qū)動(dòng)的鍛壓。這些機(jī)械包括簡(jiǎn)單的平移運(yùn)動(dòng)。</p><p>　　滾軋：滾軋是對(duì)固態(tài)金屬材料進(jìn)行初步機(jī)械加工，使其產(chǎn)生塑性變形的質(zhì)量守恒的

14、一種工藝方法。滾軋廣泛應(yīng)用在板材、薄板和結(jié)構(gòu)桁條等制造中。圖9.1(b)顯示了板材或薄板的滾軋。鑄造生產(chǎn)出的鐵錠加熱后，經(jīng)過(guò)幾個(gè)階段厚度上變薄。由于工件的寬度保持不變，工件的長(zhǎng)度將隨著厚度的變薄而變長(zhǎng)。在熱軋階段之后，最終階段是進(jìn)行冷卻，以提高表面質(zhì)量、公差，并提高強(qiáng)度。滾軋工藝中，根據(jù)需要，軋輥的外形被設(shè)計(jì)生產(chǎn)成期望的幾何形狀。</p><p>　　粉末擠壓：粉末擠壓是對(duì)粒狀材料進(jìn)行機(jī)械加工，使其產(chǎn)生塑性變形的