沖壓模具外文翻譯---影響沖壓模具壽命的因素分析

1、<p><b>　　附 錄</b></p><p>　　The study of Influence factors on dies' life</p><p>　　Because the ramming processing has the productivity to be high, the material use factor is hi

2、gh, the pressing part precision high, the complex degree is high and interchangeability good and so on characteristics, therefore, in the industrial production, applies especially in the production in enormous quantities

3、 very widely. But the ramming mold in the cold stamping processing is also essential. The ramming mold general structure is complex, the accuracy requirement is high, the production cost </p><p>　　1 The infl

4、uence ramming die life's primary factor to enhance the ramming die life, must to the mold which expires carry on the analysis, understands and grasps the expiration reason and the influence die life primary factor. T

5、hrough the research discovery, affects the ramming die life the primary factor to have the following several aspects:</p><p>　　1.1 Mold material </p><p>　　(1) mold material smelting if the quali

6、ty of die steel contains more objects or too much carbon steel, will seriously reduce the impact toughness of steel, anti-fatigue and fracture resistance, causing an early fracture die , blocks and cracking, etc. collaps

7、e. (2) mold material in the heat die machining process must be carried out in the quenching and tempering heat treatment and so on. The level of heating temperature, the length, the size of the cooling rate, the protecti

8、on measures, such as </p><p>　　1.2 Die structure (1) die form of die structure of the structure is based on the shape of stamping parts to the design of the same stamping, mold can form a very wide range of

9、 choices, if the mold structure is irrational and the stress concentration may lead to fracture failure. (2) stamping parts stamping parts of the shape of the shape of more complex structures will be more complex molds,

10、 stamping dies when the local increase wear and tear or deformation, damage, will reduce the life of mol</p><p>　　1.3 If the press situation in low-precision press-oriented, poor stiffness, high incidence of

11、 eating mold-mode and speed up the wear and tear on the life of a great impact on mold. 1.4 Use and maintenance of molds including mold installation, transportation, preservation and maintenance of lubricants, such

12、 as the use and operation.</p><p>　　2 Improve the stamping die life in an effective way of stamping, the die service life of high-mode edge can reduce the number of repair and installation time debugging to

13、ol to increase the effective working hours and raise labor productivity, reduce cost of production stampings.</p><p>　　Life of stamping dies for the impact of the main factors, there are the following types

14、of stamping dies to enhance an effective way of life </p><p>　　2.1 Selection of a suitable wear-resistant materials in general, in the stamping production stamping parts according to material and technical

15、requirements, production batch size, the premise of ensuring the economy as far as choice of materials with high wear resistance and the necessary heat treatment process. Mold materials commonly used are: (1) Cr12 stee

16、l types, including Cr12Mo, Cr12MoV: cold stamping die for a wider range of alloy tool steel, has a high hardenability, hardened and wear</p><p>　　2.2 Die Mold Surface Treatment Surface Treatment includes cr

17、emation strengthen and chemically enhanced in two ways. (1) strengthen the EDM EDM is enhanced carbide conductive material, such as electrodes, and metal in the air spark discharge between the workpiece, the use o

18、f spark discharge energy release, so that infiltration of electrode material, covering the surface of the mold to form a strengthening layer. EDM has improved the work of strengthening of the physico-chemical properties&

19、lt;/p><p>　　2.3 Optimization of Die Structure Design (1) to improve the work of die structure design reliability: in the production of not punching action is not in place or malfunction or damage to reduce th

20、e die service life of molds. Institutions such as the feed, discharge, the top pieces of the system components should have sufficient strength and rigidity, flexible movement and reliable. (2) die structure optimizatio

21、n of parameters: the choice of structural parameters directly affect the life of m</p><p>　　2.4 The proper use, maintenance and maintenance of the life of Mold, with the exception of reasonable depends on t

22、he design, the manufacture of high precision, good effect of heat treatment and press the right selection, the stamping die production of the proper use, maintenance and repair is also important in general should pay att

23、ention to the following points: (1) carefully before using the mold inspection, removal of dirt. There are die-oriented devices, lubrication should be checked sound</p><p>　　3 Proper selection of the die ma

24、terial and of the die manufacturing technique determines , to a large extent , the useful life of forming dies. Dies may have to be replaced for a number of reasons ,such as changes in dimensions due to wear or plastic d

25、eformation, deterioration of the surfacefinish, breakdown of lubrication, and cracking or breakage. In hot impression die forging , the principal modes of die failure are erosion ,thermal fatigue ,mechanical fatigue and

26、permanent(plastic) deformati</p><p>　　In erosion ,also commonly die wear , materials is actually removed from the die surface by pressure and sliding of the deforming material ,wear resistance of the die mat

27、erial , die surface temperature , relative sliding speed at the die /material interface and the nature of the interface layer are the most signficnt factors influencing abrasive die wear. Thermal fatigue occures on the s

28、urface of the die impression in hot forming and results in "heat checking" .Thermal fatigue results from cyclic</p><p>　　The design and manufacture of dies and selection of die materials are very i

29、mportant in the production of discrete parts by use of metal forming processes . The die must be made by modernmanufavturing methods from appropriate die materials in order to provide acceptable die life at a reasonable

30、cost. Often the economic success of a forming process depends on die life and die costs per piece produced . For a given application , selection of the appropriate die material depends on three types of v</p><

31、p>　　3.1 Variables related to the process itself , including factores such as size of the die cavity , type of machine used and deformation speed , initial stock and temperature , die temperature to be used , lubricat

32、ion , production rate and number of parts to be producted .</p><p>　　3.2 Variable related to the type of die loading , including speed of loafing ,impact or gradual contact time between dies and deforming me

33、tal (this contact time is esoecially important in hot forming), maximum load and pressure on the dies , maximum and minimum die temperatures, and number of loading cycles to which the dies will be subjected. </p>

34、<p>　　3.3Mechanical properties of the die material , including hardenability ,impact strengthen (if hot forming is considered) and resistance to thermal and mechanical fatigue .</p><p>　　影響沖壓模具壽命的因素分析&

35、lt;/p><p>　　由于沖壓加工具有生產(chǎn)率高、材料利用率高、沖壓件精度高、復(fù)雜程度高和互換性好等特點(diǎn),因此,在工業(yè)生產(chǎn)中,尤其在大批量生產(chǎn)中應(yīng)用十分廣泛。而沖壓模具在冷沖壓加工中又是必不可少的。沖壓模具一般結(jié)構(gòu)較復(fù)雜,精度要求高,制造成本也高。在沖壓過(guò)程中,沖壓模具由于長(zhǎng)期磨損、變形、斷裂等原因而產(chǎn)生失效,從而導(dǎo)致企業(yè)生產(chǎn)成本居高不下。因此,探索提高沖壓模具的使用壽命的有效途徑對(duì)于企業(yè)發(fā)展具有重要意義。</

36、p><p>　　1　影響沖壓模具壽命的主要因素為了提高沖壓模具壽命,必須對(duì)已失效的模具進(jìn)行分析,了解和掌握失效原因和影響模具壽命的主要因素。通過(guò)研究發(fā)現(xiàn),影響沖壓模具壽命的主要因素有以下幾個(gè)方面:</p><p>　　1.1　模具材料(1)模具材料冶煉質(zhì)量的影響若模具鋼中含有雜物較多或鋼中的碳化物過(guò)多,將嚴(yán)重降低鋼的沖擊韌度、抗疲勞強(qiáng)度和斷裂抗力,引起模具的早期斷裂、崩塊及開裂等。(2)模具材

37、料的熱處理沖模在機(jī)械加工過(guò)程中都要進(jìn)行淬火、回火等熱處理。加熱溫度的高低、時(shí)間的長(zhǎng)短、冷卻速度的大小、保護(hù)措施等工藝參數(shù)的選擇都會(huì)影響沖模的壽命。(3)工件材料的性能各種材料的硬度、強(qiáng)度、耐磨性、耐腐蝕性、塑性變形抗力、斷裂抗力、冷熱疲勞抗力等性能均有所不同,沖壓過(guò)程中不同性能的工件材料對(duì)沖壓的影響也各不相同,如沖壓硬度高的工件材料時(shí)會(huì)加快、增大模具的磨損;沖壓硬而粘的工件材料(如不銹鋼)時(shí)發(fā)熱大,易粘模,清理不及時(shí)也會(huì)加快模具磨損,降

38、低模具的使用壽命。因此模具材料必須根據(jù)工件材料來(lái)選用。</p><p>　　1.2　模具結(jié)構(gòu)(1)模具的結(jié)構(gòu)形式模具結(jié)構(gòu)是根據(jù)沖壓件的形狀來(lái)設(shè)計(jì)的,對(duì)同一沖壓件,模具的結(jié)構(gòu)形式可以有很多種選擇,若模具結(jié)構(gòu)不合理可能導(dǎo)致應(yīng)力集中而斷裂失效。(2)沖壓件的形狀沖壓件的形狀越復(fù)雜,模具結(jié)構(gòu)也會(huì)越復(fù)雜,沖壓時(shí)會(huì)加大模具的局部磨損或變形、損壞,將會(huì)降低模具的壽命。(3)模具參數(shù)模具參數(shù)有沖裁間隙、沖裁力、卸料力、搭邊值等等

39、,其中沖裁間隙對(duì)模具壽命的影響最大,如間隙合理,模具壽命長(zhǎng);間隙過(guò)大或過(guò)小,都會(huì)降低模具壽命。(4)模具的導(dǎo)向機(jī)構(gòu)模具無(wú)導(dǎo)向機(jī)構(gòu)或者導(dǎo)向精度低,剛性差,也會(huì)加劇模具的磨損,降低模具壽命。</p><p>　　1.3　壓力機(jī)狀況若壓力機(jī)的導(dǎo)向精度低、剛度差,易發(fā)生啃模和加速模具磨損,對(duì)模具的壽命影響極大。</p><p>　　1.4　模具使用和維護(hù)包括模具安裝、運(yùn)送、保存以及潤(rùn)滑劑使用和操作

40、維護(hù)等。</p><p>　　2　提高沖壓模具壽命的有效途徑在沖壓生產(chǎn)中,模具使用壽命高,可減少修模刃口的次數(shù)和安裝調(diào)試模具的時(shí)間,增加有效工作時(shí)間,提高勞動(dòng)生產(chǎn)率,降低沖壓件生產(chǎn)成本。針對(duì)影響沖壓模具壽命的主要因素,有以下幾種提高沖壓模具壽命的有效途徑: </p><p>　　2.1　選用合適的耐磨損材料一般來(lái)說(shuō),在沖壓生產(chǎn)中應(yīng)根據(jù)沖壓件材料和技術(shù)要求、生產(chǎn)批量大小,在保證經(jīng)濟(jì)性前提下,

41、盡量選用耐磨性能高的材料和必要的熱處理工藝。常用的模具材料主要有:(1)Cr12型鋼種,包括Cr12Mo,Cr12MoV:是用于冷沖壓模具較廣泛的合金工具鋼,有高的淬透性、淬硬性,耐磨損能力強(qiáng)。(2)Cr4W2MoV鋼(即120Cr4W2MoV):這種材料與Cr12型鋼種相比較,共晶碳化物細(xì)小,且分布較均勻,有較高的淬透性、淬硬性,還具有較高的力學(xué)性能和耐磨性。W、Mo、V元素有助于提高鋼的穩(wěn)定性,為采用化學(xué)熱處理提高模具壽命提供了有利

42、的條件。(3)W6Mo5Cr4V2Al鋼:硬度高,可淬硬到HRC 66～68,耐磨性好,比一般合金鋼的模具可提高壽命4倍以上。適用于沖制對(duì)模具磨損特別大的材料,如鎳鉻鈦、層壓玻璃纖維板等材料。(4)硬質(zhì)合金:硬度高,可達(dá)HRC85以上。耐磨性極好,硬質(zhì)合金模具壽命比一般工具鋼模具高30～50倍。隨著數(shù)控線切割、電火花等加工方法的廣泛應(yīng)用,硬質(zhì)合金模具的應(yīng)用范圍在不斷擴(kuò)大。當(dāng)然,模具材料耐磨性越好,一般材料價(jià)格越昂貴,加工成本也越高,所以

43、在選材時(shí)</p><p>　　2.2　模具表面強(qiáng)化處理模具表面強(qiáng)化處理包括電火化強(qiáng)化和化學(xué)強(qiáng)化兩種方法。(1)電火花強(qiáng)化 電火花強(qiáng)化是采用硬質(zhì)合金等導(dǎo)電材料作電極,在空氣中與金屬工件之間產(chǎn)生火花放電,利用火花放電時(shí)釋放的電能,使電極材料熔滲、覆蓋到模具表面,形成強(qiáng)化層。電火花強(qiáng)化改善了工作表面的物理化學(xué)性能,提高金屬表面的硬度、耐磨性、耐蝕性,模具使用壽命可延長(zhǎng)2~3倍。強(qiáng)化后模具表面硬度可達(dá)68~72HRC。(

44、2)化學(xué)強(qiáng)化 化學(xué)強(qiáng)化有滲氮處理、滲硼處理等。滲氮處理有液體滲氮、氣體滲氮和輝光離子滲氮。金屬表面通過(guò)滲氮形成硬的氮化層,硬度可達(dá)65~69HRC,滲氮表面具有高硬度、耐磨性、耐熱性、高的疲勞強(qiáng)度和耐蝕性。滲氮用于模具,其壽命比未氮化的提高2~3倍。滲氮深度可達(dá)0.12mm,硬度1200HV。由于滲氮后在模具表面形成一層氮化物保護(hù)膜,大大降低了摩擦系數(shù),可提高模具壽命。滲硼處理是將零件放在熔化了的硼砂(Na2B4O7)和碳化硅混合物中,

45、在一定溫度下,經(jīng)過(guò)一定時(shí)間,在零件表面形成了單相的Fe2B或以Fe2B為主,有少量的FeB的雙相滲硼層。這兩重化合物具有很高的硬度和很小的摩擦系數(shù),可提高模具耐磨性和使用壽命</p><p>　　2.3　優(yōu)化沖模結(jié)構(gòu)設(shè)計(jì)(1)提高設(shè)計(jì)模具結(jié)構(gòu)的工作可靠性:在沖壓生產(chǎn)中不會(huì)因動(dòng)作不到位或誤動(dòng)作而損壞模具或者降低模具使用壽命。如送料機(jī)構(gòu)、卸料、頂件系統(tǒng)零件應(yīng)有足夠的強(qiáng)度和剛性,動(dòng)作靈活、可靠。(2)優(yōu)化模具結(jié)構(gòu)參數(shù):

46、結(jié)構(gòu)參數(shù)的選擇直接影響模具的壽命。如沖裁間隙,應(yīng)按所沖零件使用要求和材料選用合理沖裁間隙,過(guò)大或過(guò)小的沖裁間隙都會(huì)加大模具磨損,降低使用壽命。(3)針對(duì)不同模具結(jié)構(gòu)選用合理的導(dǎo)向方式,以提高模具的壽命。(4)從設(shè)計(jì)和工藝等方面保證模具零件的質(zhì)量:如果工作表面過(guò)于粗糙,成形模具的圓弧刃口有棱不光滑,會(huì)使沖裁毛刺加大、成形件表面拉毛、拉傷,都會(huì)加快模具磨損,降低其使用壽命。</p><p>　　2.4　正確使用、維護(hù)

47、和保養(yǎng)模具模具的使用壽命,除取決于合理的設(shè)計(jì)、高的制造精度、良好的熱處理效果以及正確選用壓力機(jī)外,沖壓生產(chǎn)中模具的正確使用、維護(hù)和保養(yǎng)也很重要,一般應(yīng)注意以下幾點(diǎn):(1)使用模具前應(yīng)認(rèn)真檢查,清除臟物。有導(dǎo)向裝置的模具,應(yīng)檢查潤(rùn)滑狀況是否良好。(2)定期檢修壓力機(jī),保證壓力機(jī)精度。使用前按規(guī)程對(duì)壓力機(jī)進(jìn)行空運(yùn)轉(zhuǎn)認(rèn)定。(3)毛坯表面要清潔,如有必要,還可以均勻的涂以潤(rùn)滑劑。(4)按安裝程序安裝模具,無(wú)導(dǎo)向裝置的模具和導(dǎo)板模,要正確調(diào)整間隙

48、。(5)凸模和凹模刃口磨損后要及時(shí)刃磨,防止迅速擴(kuò)大刃口磨損深度而降低沖壓件質(zhì)量和模具壽命。(6)大量生產(chǎn)時(shí),中、小模具必須有備份,以便輪換使用,保證正常生產(chǎn)。 (7)沖壓工人使用的送、取料操作工具,應(yīng)用軟金屬制成,以防發(fā)生意外事故而損壞模具。(8)運(yùn)送模具要輕拿輕放,決不允許亂扔亂碰,以防損壞模具刃口及導(dǎo)向裝置。對(duì)于超過(guò)50公斤重量的大中型模具,應(yīng)配有起重螺釘?shù)仍O(shè)施,便于搬運(yùn)。(9)模具使用后,應(yīng)清除廢料及臟物,并在刃口和導(dǎo)向部分涂潤(rùn)

49、滑油,保證模具的清潔而不致生銹。(10)不生產(chǎn)的模具應(yīng)按規(guī)定碼放。每套模具要建管理卡片,記錄使用、</p><p>　　3 成形模具的使用壽命在很大程度上取決于對(duì)模具材料和模具的制造技術(shù)的正確選樣。由于某些原因，模具可能不得不更換。例如，由于磨損或塑性變形而使尺寸發(fā)生改變，模具表面光潔度降低并出現(xiàn)潤(rùn)滑故障以及裂紋或破裂．在熱壓模鍛中．模具失效的主要模式是腐蝕、熱疲勞、機(jī)械疲勞和水久性塑性變形。</p>

50、<p>　　腐蝕，通常又稱為模具磨損，實(shí)際上是在壓力作用下，模具表面材料產(chǎn)生的變形和剝落。影響模具磨損的主要原因包括；變形材料的滑動(dòng)、模具材料的抗磨性、模具表面的溫度以及模具和材料表面的相對(duì)滑動(dòng)速度、接觸層的性質(zhì)。</p><p>　　熱成形加工會(huì)產(chǎn)生熱裂紋并使模具模腔的表面發(fā)生熱疲勞。這是因?yàn)榕c熱變形材料接觸．模具表面產(chǎn)生了周期性屈服。這種接觸會(huì)引起模具表層的膨脹，由于溫度梯度的急劇變化，表層還會(huì)

51、承受壓應(yīng)力。如果溫度足夠高。這些壓應(yīng)力會(huì)使表層變形。當(dāng)模具表面冷卻時(shí)，會(huì)產(chǎn)生反向應(yīng)力，使模具表層受拉。這種狀態(tài)循環(huán)往復(fù)使模面龜裂，形成熱裂紋。</p><p>　　在模具過(guò)敏和局部應(yīng)力過(guò)高等情況下臺(tái)發(fā)生機(jī)械疲勞，使模具破裂或產(chǎn)生裂紋。在成形加工過(guò)程中，由于加載、減載，模具承受著交變應(yīng)力，這將引起開裂并最終導(dǎo)致失效。</p><p>　　在給定成形工藝的條件下，模具材料的機(jī)械性能對(duì)模具的壽命

52、和模具的損壞影響很大。一般而言，最具影響的是加工過(guò)程的溫度。所以，用于冷卻成形加工工藝的模具材料與用于熱成形加工的材料應(yīng)該差別很大。</p><p>　　用金屬成形工藝加工單件、小批產(chǎn)品時(shí)，模具的設(shè)計(jì)、制造和材料的選擇是非常重要的。為了使模具的成本合理、壽命令人滿意，必須用合適的模具材料和用現(xiàn)代的制造方法來(lái)制造模具。成形加工的經(jīng)濟(jì)效益主要取決于模具壽命和每件模具的成本。因此，選擇合適的模具材科要考慮以下三方面的因

53、素。</p><p>　　(1)與加工工藝本身有關(guān)的因素，包括模腔尺寸、所用機(jī)器形式和交形速度、毛坯尺寸和溫度、模具溫度、潤(rùn)滑、生產(chǎn)效率和要生產(chǎn)的零件數(shù)量。</p><p>　　(2)與模具加載形式相關(guān)的因素，包括加載速度，即模具與正在變形的金屬之間的沖擊時(shí)間或逐漸接觸的時(shí)間(在熱變形加工中，這種接觸時(shí)間顯得特別重要)，在模具上的最大載荷和壓力， 最大和最小的模具溫度以及模具將要承受的加