【正文】 under rough casting or forging. After normalizing or hardening and performance characteristics are after: the carrying capacity per unit area in the medium, the robust performance with good, easy to run together, the bending strength of the tooth root more stable, higher safety factor. Carbon content of a selected medium carbon steel and low alloy steel to produce low carbon.2. Normalizing or quenching and then express the surface hardening of hardened gear materialsHardened gear materials such gear blank, the situation can be selected according to the bearing castings or forgings, welded structure can be applied. Welded structure gears from the rim (forging), spoke (steel or forgings), hub (castings or forgings) with three parts of the rough shape after welding process. After the final heat treatment after welding gear, the body part has good strength and toughness, some of the tooth with high bearing capacity. This normalizing or hardening after quenching the hardened gearrow table, the selection with the same hardened gears, but can control the carbon content of these steels in %, could face more barriers to take care of all aspects of performance. These materials are then quenched and the gear surface hardening line.3. Carburized hardened gear materialsThis gear blanks are forged, after carburizing and quenching, the strength and toughness and has good carrying capacity, and more stable performance. Generally use low Tianjin or low in Tianjin casehardened steel to manufacture. Selection of the problems that need attention1. Metallurgical qualitySoft or medium hard gear tooth failure is characterized by pitting spelling, plastic deformation or even broken tooth, hardened gears hardened layer occurs off or broken tooth. If the steel in the presence of more harmful gases and nonmetallic inclusions, the stress will be concentrated in the weak links or the small crack, as the origin of the various fatigue crack, leading to early failure of gear. Therefore, to ensure the quality of metallurgical materials is to avoid overloading the early failure of the important measures to gear one. Using a vacuum casting furnace melting, vacuum melting vacuum degassing process or double vacuum melting furnace and then electroslagremelting can greatly reduce the oxygen and hydrogen content. Nonmetallic inclusions will also be greatly reduced, but also to take measures to change the shape and size and distribution of inclusions in a good state test so that, after vacuum treatment .Material properties of the atmosphere than the melting of the material to to 1 times.2. The size of the original grain size and growth tendencies Heavy gear the selected material, though both are essentially finegrained steel, but some of the production process of the heating temperature higher than the fine grain nature of austenite grain coarsening temperature of the standards required (930 ℃), or in the heat of the actual operation does not occur inevitably local overheating.3. Harden ability used to ensure the H SteelIn recent years, foreign harden ability had introduced a more stable, with a more narrow harden ability guaranteed harden ability of steel that is H steel, to a fundamental stability in the quality heat treatment of gears. For example, in aviation, marine, automotive and other products had to switch gears H steel, required H Steel Can permeability of the bandwidth ≤ 6 HRC, oxygen content ≤ 20ppm, the original grain size 5. Simply H of steel is characterized by:(1) The reasonable properties that affect the harden ability of carbon and alloy element content of the cooperation。 熱后機(jī)加工： 主動(dòng)錐齒輪的熱后機(jī)加工工藝過(guò)程 After the active thermal bevel gear machining process山東交通學(xué)院熱 后 機(jī) 加 工 工 藝 過(guò) 程 卡 片零件名稱(chēng)主動(dòng)錐齒輪材料編號(hào)22CrMoH工序號(hào)工序名稱(chēng)基準(zhǔn)及技術(shù)要求設(shè)備工夾具13研中心孔鉆床鉆夾具14磨外圓，外圓磨床磨夾具15磨外圓，外圓磨床磨夾具16磨花鍵底徑，有效長(zhǎng)68mm，花鍵底直徑為52mm，銑床銑夾具17磨花鍵兩側(cè)有效長(zhǎng)為68mm，花鍵齒寬為10mm，銑床銑夾具18過(guò)螺紋螺紋長(zhǎng)31，普通車(chē)床車(chē)夾具19終檢在檢查機(jī)上檢驗(yàn)與配偶齒輪的嚙合印痕處數(shù)更改文件號(hào)簽字/日期標(biāo)記磨削加工是用高速回轉(zhuǎn)的砂輪或其他磨具以給定的背吃刀量（或稱(chēng)切深），對(duì)工件進(jìn)行加工的方法。淬火的目的是獲得馬氏體，以提高鋼的強(qiáng)度、硬度和耐磨性等力學(xué)性能，為后面的熱處理作好組織準(zhǔn)備。分解是指零件周?chē)橘|(zhì)中的滲劑分子發(fā)生分解，形成滲入元素的活性原子。鉆頭刃磨時(shí)，應(yīng)盡量使麻花鉆的兩主切削刃磨得對(duì)稱(chēng)，使兩個(gè)主切削刃的徑向力相互抵消，以防止鉆頭引偏及孔徑擴(kuò)大。有兩種銑削方法：（1）分兩次銑出花鍵，即先銑側(cè)面，然后再銑內(nèi)徑。銑削主要用于加工各種平面、各種溝槽、齒輪、齒條和成形面等。二、滾齒滾齒是齒形加工中生產(chǎn)率較高、應(yīng)用最廣的一種方法，在這里我們簡(jiǎn)單介紹一下。（2）齒形加工一、齒形加工方法按加工中有無(wú)切削，可分為無(wú)切削加工和有切削加工兩大類(lèi)。齒坯加工，在齒輪的整個(gè)加工過(guò)程中占有重要的位置，包括切齒前的各工種序，如車(chē)、銑、鉆、攻絲等這樣一類(lèi)的加工。變化其中的任一要素就成為另一工步。它們是工序、安裝、工位、工步和走刀，其中工序是工藝過(guò)程中的基本單元。（5）完工檢驗(yàn)：按鍛件圖執(zhí)行。其中等溫退火可以縮短退火時(shí)間，得到的組織更均勻，特別是對(duì)某些合金鋼，生產(chǎn)中常用等溫退火來(lái)代替完全退火或球化退火。通常模鍛工時(shí)長(zhǎng)，沖切工時(shí)短，故切邊生產(chǎn)率受到模鍛生產(chǎn)率的限制）。胎模鍛是介于自由鍛和模鍛之間的一種工藝。為了減輕模鍛設(shè)備的負(fù)擔(dān)或充分利用現(xiàn)有模鍛設(shè)備，簡(jiǎn)化鍛模結(jié)構(gòu)，有些模鍛件的制坯工步也在自由鍛設(shè)備上完成。按原則（3）有L/D=～，即L=(～)D。鍛造不僅可以獲得預(yù)定的坯件形狀，而且可以使粗大的晶粒破碎，晶粒細(xì)化，提高金屬的力學(xué)性能，還可以節(jié)省材料，生產(chǎn)率高。22CrMoH屬于低碳鋼。這些元素的主要作用是：加入錳、硅、鉻、鎳元素為強(qiáng)化鐵素體；加入釩、鈮、鈦、鋁等元素為細(xì)化鐵素體晶粒；合金元素使S點(diǎn)左移，增加珠光體數(shù)量；加入碳化物形成元素（釩、鈮、鈦）及氮化物形成元素（鋁），使細(xì)小化合物從固溶體中析出，產(chǎn)生彌散強(qiáng)化作用。因此，齒輪材料應(yīng)該有足夠的齒面硬度，已獲得抗點(diǎn)蝕、抗磨粒磨損、抗膠合和抗塑性形變的能力；而齒心要韌，在變載荷和沖擊載荷作用下有足夠的抗彎疲勞折斷能力；同時(shí)還要有良好的機(jī)械加工和熱處理性能。、從動(dòng)錐齒輪嚙合圖 Host, driven bevel gear meshing chart汽車(chē)正常行駛時(shí)，發(fā)動(dòng)機(jī)的轉(zhuǎn)速通常在2000至3000r/min左右，如果將這么高的轉(zhuǎn)速只靠變速箱降低下來(lái)，那么變速箱內(nèi)齒輪副的傳動(dòng)比則需很大，而齒輪副的傳動(dòng)比越大，兩齒輪的半徑比也越大，換句話(huà)說(shuō)，也就是變速箱的尺寸會(huì)越大。易造成齒面的磨損，點(diǎn)蝕等，嚴(yán)重時(shí)會(huì)使輪齒折斷。齒輪材料除必須滿(mǎn)足工作條件，還要考慮齒輪尺寸的大小、毛坯的成形方法及熱處理和制造工藝。低碳合金鋼比碳素鋼具有更高的力學(xué)性能和更好的淬火性能，重型汽車(chē)的主從動(dòng)錐齒輪傳動(dòng)載荷較大，沖擊大，因此，在傳遞大動(dòng)力，并要求減小尺寸與質(zhì)量，提高軸頸的耐磨性，常采用合金鋼。中等或中等以下尺寸要求較高齒輪常選用鍛造毛坯。機(jī)械加工零件的毛坯種類(lèi)主要有鑄件、鍛件、焊接件、沖壓件以及各種軋制材料。雖然該方法生產(chǎn)率高，操作簡(jiǎn)單，切口無(wú)金屬損耗，但是剪切后坯料局部會(huì)被壓扁，端面不平整，剪切面常有毛刺和裂紋。模鍛需要借助模具，加大了投資，因此不適合單件和小批量生產(chǎn)。在此，我們采用摩擦壓力機(jī)。制坯工序若采用熱滾鍛代替，滾鍛制坯后接著模鍛，變二火型為一火成型，可節(jié)約原材料及能源。方法：首尾盤(pán)各放置一件樣品，其余每十二盤(pán)放置一件樣品；設(shè)備：高溫爐；加熱溫度：Ⅰ區(qū)860℃、Ⅱ區(qū)940℃、Ⅲ區(qū)940℃；保溫時(shí)間：234min；速冷(空氣鼓風(fēng))至650℃，保溫234min。而且，用中心孔作為定位基準(zhǔn)，就能夠最大限度的在一次安裝中加工出多個(gè)外圓和端面，這也符合基準(zhǔn)統(tǒng)一的原則。例如，在車(chē)床上加工一批軸，既可以對(duì)每一根軸連續(xù)地進(jìn)行粗加工和精加工，也可以先對(duì)整批軸進(jìn)行粗加工，然后再依次對(duì)它們進(jìn)行精加工。一個(gè)工步可包括一次或數(shù)次走刀。一般情況下，以齒輪孔和端面為齒形加工的基準(zhǔn)面，所以齒坯精度中主要是對(duì)齒輪孔的尺寸精度和形狀精度、孔和端面的位置精度有較高的要求；當(dāng)外圓作為測(cè)量基準(zhǔn)或定位、找正基準(zhǔn)時(shí)，對(duì)齒坯外圓也有較高的要求。按其加工成形原理可分為成形法和展成法兩種。一般滾齒后可直接得到9級(jí)精度的齒輪，當(dāng)采用AA級(jí)以上的齒輪滾刀和高精度滾齒機(jī)時(shí)也可以加工出7級(jí)以上精度的齒輪，甚至加工出4級(jí)精度的齒輪。銑削加工精度一般可達(dá)到IT8～I(xiàn)T7，～，一方面使刀具的壽命下降，另一方面引起周期性的沖擊和振動(dòng)。精度不高的花鍵可在銑床上用分度頭在兩頂尖中安裝，用成