外文翻譯--制造業(yè)用于提高表面光潔度和減少切削力的拋丸清理機

1、<p>　　Micro shot blasting of machine tools for improving surface finish and reducing cutting forces in manufacturing</p><p>　　D.M. Kennedy *, J. Vahey, D. Hanney</p><p>　　Faculty of Enginee

2、ring, Dublin Institute of Technology, Bolton Street, Dublin 1, Ireland</p><p>　　Received 5 January 2004; accepted 3 February 2004</p><p>　　Available online 13 April 2004</p><p><

3、b>　　Abstract</b></p><p>　　Micro blasting of cutting tips and tools is a very effective and reliable method of advancing the life of tools under the action of turning, milling, drilling, punching and

4、 cutting. This paper outlines the ways in which micro blasted tools, both coated and uncoated have benefited from shot blasting and resulted in greater productivity, lower cutting forces, improved surface finish of the w

5、ork pieces and less machine downtime. The process of micro blasting is discussed in the paper. Its effective</p><p>　　Control of the process to provide repeatability and reliability in the shot blasting unit

6、 is discussed. Comparisons between treated and untreated cutting tools are made and results of tool life for these cutting tips outlined. The process has shown to be of major benefitto tool life improvement. 2004 Elsevie

7、r Ltd. All rights reserved.</p><p>　　Keywords: Micro shot blasting; Surface finish; Machine tools</p><p>　　1. Introduction</p><p>　　Many modern techniques have been developed to enh

8、ance the life of components in service, such as alloying additions, heat treatment, surface engineering, surface coating, implantation processes, laser treatment and surface shape design. Processes such as thin film tech

9、nology, plasma spraying, vacuum techniques depositing a range of multi-layered coatings have greatly enhanced the life, use and applications of engineering components and machine tools. Bombardment with millions of micro

10、 shot rangi</p><p>　　2. Method of operation</p><p>　　One of the primary ways that components fail in ervice is through fatigue. This is closely associated with cyclic stresses and accelerated by

11、 tensile stresses, micro crack propagation and stress corrosion cracking. Cracks reduce the cross section of a material and eventually it will fail to support the applied loads. One simple method of reducing failure by f

12、atigue is to arrest these tensile stresses by inducing compressive stresses into a surface. The benefits obtained with shot peening are a d</p><p>　　Poor machining of materials can result in residual stresse

13、s accruing at the surface. Rough surfaces have deeper notches, where cracks can initiate due to tensile stress concentrations at these points. Many standard machining processes such as grinding, milling, turning, and coa

14、ting processes such as electroplating induce residual tensile stresses in surfaces and this can lead to early failure of components. Further tensile loading in service would lead to early failure and this can be prevente

15、d </p><p>　　(i) resistance to fatigue fracture;</p><p>　　(ii) resistance to stress corrosion;</p><p>　　(iii) a change in residual stresses;</p><p>　　(iv) modification o

16、f surface finish.</p><p>　　It is a cold working process involving bombarding powders such as ceramics, glass and metals of mainly spherical shapes against surfaces and can be used in conjunction with other p

17、rocesses. The main stages involved in this dynamic process include elastic recovery of the substrate after impact, some plastic deformation of the substrate if the impact pressure exceeds the yield stress, increased plas

18、tic deformation due to an increase in impact pressure and finally some rebound of the shot due to a </p><p>　　3. Experimental work</p><p>　　Tool materials such as Tungsten Carbide, High Speed St

19、eels used in milling and turning tools were subjected to the micro peening process using different shot media (ceramic and glass bead) and shot size. Tests prior to and following the blasting process were conducted to a

20、scertain any improvements resulting from the process.</p><p>　　The micro shot peening unit is shown in Photo 1 it incorporates an air filter, pressure regulator and gauge, air flow regulator, pressurised bla

21、st media container and a venturi blast nozzle for directing the stream of micro shot. The unit is PLC controlled and a stepper motor, used to drive a lead screw, is used to move the blast nozzle across the sample in orde

22、r to control media shot coverage. </p><p>　　The blast nozzle can also be rotated to allow shot media to strike the samples at different angles. Tests undertaken include surface finish and roughness measureme

23、nt, machining tests on standard lathes and mills, hardness tests, cutting forces on turning operations, tool wear and the determination of surface finish of the work pieces machined. Figs. 2 and 3 show a typical high spe

24、ed steel (HSS) tip prior to and following the micro shot peening process using ceramic bead at a pressure of 5.5 bar.</p><p>　　4. Experimental results</p><p>　　Testing of treated and untreated c

25、utting tips and tools was conducted on HSSs for turning and milling as well as coated and uncoated carbide inserts. A dynamometer was used to measure cutting forces on the turning tool (Lathe). The cutting process consis

26、ted of a depth of cut of 2 mm on a standard bright mild steel specimen over a length of 750 mm while milling tests consisted of machining a 25_25_150 mm piece of mild steel using a depth of cut of 1 mm with a slot millin

27、g cutter of 18 mm diameter</p><p>　　4.1. Micro hardness tests</p><p>　　Combined Vickers micro hardness tests gave the results in Table 1. for both treated and untreated HSS cutting tips.</p&g

28、t;<p>　　4.2. Surface roughness values</p><p>　　In all surface roughness tests conducted, the micro blasted surface gave an improved surface roughness value. Surface roughness and profile tests were ca

29、rried out on both a Talyor Hobson Tallysurf instrument and a non contact surface profileometer. Surface roughness details of a typical untreated HSS cutting tip and a treated one are shown in Figs. 4 and5 and Table 2 sho

30、ws the results of surface measurement values for other cutting tips and tools and workpieces. Fig. 6 shows an uncoated carbide </p><p>　　and5 and Table 2 shows the results of surface measurement values for o

31、ther cutting tips and tools and workpieces. Fig. 6 shows an uncoated carbide cutting tip which was not subjected to micro blasting. The flank wear was measured using an optical microscope and the value recorded was 150 l

32、m after 676 s of machining. Fig. 7 shows an uncoated carbide tip subjected to micro blasting. The flank wear in this case is only 90 lm for the same machining time.</p><p>　　4.3. Dynamometer tests</p>

33、<p>　　Figs. 8 and 9 show the comparison for Dynamometer results for HSS in the treated (micro blasted) and untreated states with relevant comments.</p><p>　　Similar profiles are shown for coated and un

34、coated turning tips in both the treated (micro blasted) and untreated conditions in Figs. 10–13. In all cases, the micro blasted tips provided an increase in cutting tip life with lower cutting forces recorded.</p>

35、<p>　　5. Conclusions</p><p>　　This research work has shown that micro shot blasting of cutting tips and tools has a very positive effect on component surfaces by increasing toughness, operating life,

36、improving hardness and surface finish. From the tests conducted, it is obvious that the process affects the residual stresses at or near the surface in a beneficial way by inducing compressive stresses on the substrates

37、tested. The micro blasting process is very simple to apply and economical to use. The mechanical properties of</p><p>　　References</p><p>　　[1] Impact. Bloomfield, CT: Metal Improvement Company;

38、 Fall 1989.</p><p>　　[2] Zimmerli FP. Heat treating, setting and shot-peening of mechanical</p><p>　　springs. Metal process; June 1952.</p><p>　　[3] Eckersley JS, Ferrelli B. Using

39、shot-peening to multiply the life of</p><p>　　compressor components. In: The shot peener, International newsletter</p><p>　　for shot-peening surface finishing industry, vol. 9, Issue No.</p&g

40、t;<p>　　1; March 1995.</p><p>　　[4] Almen JC. J.O. Almen on hot blasting. General motors test, US</p><p>　　Patent 2,350,440.</p><p>　　[5] Champaigne J. Controlled shot peenin

41、g. Elec Inc., Report; 1989.</p><p>　　制造業(yè)用于提高表面光潔度和減少切削力的拋丸清理機</p><p><b>　　摘要</b></p><p>　　在旋轉，銑削，鉆孔，沖孔和切削運動中，微拋丸切削技巧和工具是一種提高工具壽命的非常高效并且可靠的方法。本文概述了應用微拋丸工具的方式，微拋丸對有無鍍膜工件的益

42、處，并且創(chuàng)造了更大的生產力，降低了切應力，提高了工件的表面光潔度，減少了機器的停機時間。本文對微拋丸過程進行了討論。它的效率取決于包括彈丸媒體和型號在內的許多參數(shù)，碰撞力學和通過微拋丸單元的彈丸的應用程序。對控制流程提供的可重復性和可靠性的爆破裝置進行了探討。處理和未經(jīng)處理的刀具的做出了對比，切割技巧對刀具壽命的影響做出了概述。這個過程體現(xiàn)了提高工具壽命的主要好處。</p><p>　　2004愛思唯爾有限公司保

43、留所有權利。</p><p>　　關鍵詞:微噴丸清理,表面光潔度;機床</p><p><b>　　介紹</b></p><p>　　許多現(xiàn)代技術已經(jīng)開發(fā)出來加強服務組件的壽命，例如添加合金，熱處理，表面工程，表面涂層，移植過程，激光治療以及表面外形設計。例如薄膜技術，等離子噴涂，沉淀多層涂料的真空技術都大大加強了壽命，工程和應用程序組件和機床

44、使用。通過控制過程用數(shù)以百萬計的大小在4到50微米的微拋丸撞擊可以顯著提高組件的使用壽命。標準噴丸技術首次使用時在20世紀30年代提高別克和凱迪拉克引擎氣門彈簧的生產過程中，但在此之前該技術就是被鐵匠和刀制造商所熟知的來提高他們工具和武器切削刃韌性的過程。當今，切割技巧和工具可以通過微拋丸清理它們的表面的過程來引導壓縮參與應力而被大大提高。鉆頭，車削頭，銑削頭，沖頭，刀刃，切片機，葉片以及一系列的其他工作部分都可以受益于該過程。<

45、/p><p>　　機器和引擎中的標準組件，例如離合器，柴油機，軸，凸輪以及動態(tài)組件等都可以通過該過程提高。由Eckersley和Ferrelli所述，例如壓縮機組件的疲勞壽命通過拋丸處理可以顯著增加。其他因素，例如抗疲勞強度，微裂紋閉合，減少腐蝕以及提高表面光潔度都可以被作為噴丸的結果而被設計進組件當中。不僅可以做到切削刀具表面光潔度的提高，而且由這些刀具加工的工件的表面光潔度作為該技術的一個成果也得到了提高。工程材

46、料中，例如工具鋼，硬質合金，陶瓷，涂層硬質合金，通過聚合物甚至橡膠（彈性物）都可以受益。這個過程的關鍵要求是開發(fā)一個自動化微拋丸的工藝過程來適用于噴漆柜或者標準拋丸位置。</p><p>　　拋丸材料，大小和質量，操作壓力，操作速度，動能，密度，覆蓋時間都要被完美優(yōu)化一系列材料。這個過程是一種視線方法卻可以應用于復雜外形例如鉆孔。</p><p><b>　　操作方法</b

47、></p><p>　　服務組件損壞的主要原因之一是疲勞使用。這是與循環(huán)應力密切相關,加速了抗拉應力，微裂紋擴展和應力腐蝕開裂。裂紋減少材料的橫截面，最終它將無法支持應用加載。減少疲勞的失敗的一個簡單方法是通過誘導壓應力到表面來停止這些拉伸應力。拋丸加工直接產生的好處是一個組件產生的殘余壓應力。典型的鏡頭的表面是圖1所示。在由阿爾門[4]描述的裂紋出現(xiàn)之前，任何應用拉伸加載將不得不克服殘余壓應力。</

48、p><p>　　不良的加工材料會導致殘留表面壓力積累。粗糙表面有更深層次的等級，在這些點，由于拉應力會產生裂紋。</p><p>　　許多標準磨削，銑削、車削和涂層工藝例如電鍍等加工過程，在表面產生殘余拉應力，這可能會導致早期失效的組件。進一步拉伸加載服務會導致早期失效，這可以防止噴丸加工和微拋丸組件表面。</p><p>　　微拋丸處理將改變以下材料表面：</p

49、><p><b>　　抗疲勞斷裂；</b></p><p><b>　　抗應力腐蝕；</b></p><p><b>　　殘余應力的變化；</b></p><p><b>　　修改的表面光潔度。</b></p><p>　　這是一個包括

50、轟擊粉末的冷加工過程，例如陶瓷，玻璃，金屬表面的主要是球形的形狀并且可用于與其他進程。參與這一動態(tài)過程的主要階段包括彈性恢復后的基質影響，如果壓力超過屈服應力的影響而使得一些基體的塑性變形，由于彈性能量的釋放，在影響最后噴丸的一些反彈的壓力，增加了塑性變形。一些關鍵設計微噴丸加工過程的特性，包括噴丸的大小、形狀、硬度、密度、耐久性、角度的影響、速度和強度。所有這些參數(shù)會影響產生的殘余壓應力。</p><p>&l

51、t;b>　　實驗工作</b></p><p>　　應用與銑削和車削工具中的工具材料如碳化鎢，高速鋼，是受到微噴丸過程使用不同的拋丸媒體和拋丸大小。測試之前和之后進行了拋丸過程確定造成的任何改進過程。</p><p>　　微噴丸加工單位是圖1所示包含一個空氣過濾器，壓力調節(jié)器，和壓力機，空氣流量調節(jié)器，壓力容器拋丸媒體，文丘里噴嘴來指導微流噴射。此單位是PLC控制和步進電機

52、，用于驅動絲杠，用于移動拋丸噴嘴來控制拋丸噴射媒體。噴嘴也可以允許旋轉，讓媒體達成樣品在不同角度噴射。包括表面光潔度和粗糙度進行測試測量、車床加工測試標準，碾磨，硬度測試，切削應力，刀具磨損，加工的工件表面光潔度測定。圖2和圖3是一種典型的高速鋼之前和在5.5bar壓力下用陶瓷珠微拋丸加工過程之后的情況。</p><p><b>　　實驗結果</b></p><p>

53、　　經(jīng)過處理和未經(jīng)處理的切割技巧和工具在高速鋼上進行車削和銑削以及有涂層或沒涂層的嵌入合金的測試。在車刀上用測力計測量切削力。切削過程用一個標準為2毫米低碳鋼試樣，其長度為750毫米，銑削時測試用加工一塊25*25*150毫米低碳鋼，加工1毫米的深度，槽銑刀直徑18毫米。表面粗糙度的測量分別在機械零部件加工之前和之后進行，以此來確定切削技巧治療是否比未經(jīng)處理的技巧帶來更優(yōu)越的性能。微硬度測試也測試了在微噴丸加工過程之后是否能增加表面硬度

54、。噴射角度在90度的影響是提供了最佳抗壓層[5]。噴射速度的影響很大程度上是依賴于表面噴嘴的大小,空氣壓力和基質之間的距離。曝光時間是適當?shù)慕o予足夠的覆蓋率的基質,這是決定于阿爾門帶飽和時間，工件縮進時間和視覺外觀。堅硬的材料,如碳化物將顯然需要更長的曝光時間或噴射媒體。微噴丸媒體使用的陶瓷珠直徑約40 微米提供高沖擊強度和硬度。</p><p><b>　　微硬度測試</b></p&

55、gt;<p>　　處理和未經(jīng)處理的高速鋼切削技巧結合維氏顯微硬度測試結果在表1列出。</p><p><b>　　表面粗糙度值</b></p><p>　　在所有表面粗糙度進行的測試中，微拋丸處理可以得到一個改進的表面粗糙度值。</p><p>　　一個典型的未經(jīng)處理的高速鋼刀片和一個處理的表面粗糙度的細節(jié)如圖4所示，圖5以及表格

56、2顯示了其他切削表面測量值的結果。</p><p>　　圖6顯示了一個裸露的硬質合金刀片并沒有受到微拋丸噴射。側面磨損是由光學顯微鏡測量的，數(shù)值是在加工676s以后記錄的，數(shù)值是150微米。圖7顯示了一個裸露的硬質合金受到微拋丸處理。相同的加工時間，本例中的側面磨損只有90 微米。</p><p><b>　　測功器測試</b></p><p>

57、;　　圖8和圖9顯示測功器的比較處理和未經(jīng)處理的高速鋼的狀態(tài)與相關評論的結果。</p><p>　　類似的顯示有涂層和無涂層的以及在經(jīng)過處理(微拋丸)和未經(jīng)處理的資料在圖10 – 13。</p><p>　　在所有情況下，微拋丸技巧提供了一個刀片在較低的切削力工作的壽命增加記錄。</p><p><b>　　結論</b></p>

58、<p>　　本研究工作表明,微噴丸的技巧和工具組件通過增加韌性、使用壽命、提高硬度和表面光潔度對表面有非常積極的影響。從實驗中可以看出，很明顯,這一過程通過在基質上影響殘余應力達到或接近表面以有益的方式誘導壓應力。微拋丸過程是非常簡單的應用和非常經(jīng)濟的。基板的機械性能將決定處理的類型,即硬度、速度、應用程序時間來獲得這一過程的最大受益。在某些情況下，作者報道受到標準拋丸提高4到10倍疲勞壽命的動態(tài)機器零件。需要進行進一步測試在