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鈦在泥漿和超聲波鉆探加工中的比較
R. Singh a J.S. Kabob
1機(jī)械與生產(chǎn)工程系，GNDE學(xué)院盧迪亞納141006，印度
2機(jī)械工程系，旁遮普大學(xué)，帕 舍 拉147004，印度
摘要
本文首先回顧了鈦及其合金在3種不同的泥漿（即：碳化硅，碳化硼和氧化鋁）和超聲鉆削中相同的機(jī)械加工背景下的加工。其后的實驗研究提出了利用超聲波鉆對鈦（TITAN15生產(chǎn)，ASTM標(biāo)準(zhǔn)號排練室）和鈦合金（TITAN31，美國ASTM Gr.5）加工5mm直徑孔的生產(chǎn)。這意味著具有3種不銹鋼、鈦和高速鋼的固體工具的20千赫壓電式換能器的使用，將作業(yè)于碳化硅，碳化硼和氧化鋁漿。該給出的數(shù)據(jù)包括對材料去除率和刀具磨損率的主要作用影響情況。結(jié)果表明，硼碳化物漿和不銹鋼工具對材料去除率是最佳的工具。在超聲波加工中工件的相對硬度也影響了材料的去除速率。
關(guān)鍵詞：泥漿 鈦合金 超聲波鉆 電式換能器 去除速率
1。介紹
鈦合金通常被視為當(dāng)中最困難加工的工件材料，盡管硬度較低（如鈦6 / 4?350高壓退火）。這是因為他們的導(dǎo)熱系數(shù)低，熱可以集中在切削區(qū)（鈦6 / 4熱有熱電導(dǎo)率對AISI 405不銹鋼11W/mK），高化學(xué)反應(yīng)在溫度升高的趨勢下形成局部剪切帶。鈦及其合金作為難加工材料的標(biāo)志（維爾馬等。，2003）。不幸的是，鈦的加工是普遍比較困難，因而即使只有少量材料可能會被去除。對于機(jī)械加工來說生產(chǎn)成本也是一個重要的比例參數(shù)。鈦及其合金非常流行，廣泛應(yīng)用于航空航天，海洋天然氣渦輪發(fā)動機(jī)和醫(yī)療。鈦合金導(dǎo)熱性差延緩了散熱，在工件內(nèi)表面產(chǎn)生一個非常高的溫度嚴(yán)重影響了工具壽命（Cornfield等。，1999）。鈦工具在溫度升高的化學(xué)反應(yīng)和工具材料，或是迅速溶解或化學(xué)反應(yīng)過程中而造成破碎和失效（維爾馬等。，2003）。這些特征組合是低彈性模量鈦，它允許工件更大的變形，并再次增加了加工這些合金的復(fù)雜性（中小企業(yè)，1985年）。
傳統(tǒng)加工過程從而無法提供對鈦合金良好的加工特性。商業(yè)這些合金加工是利用放電加工，這給好材料去除率、準(zhǔn)確性和表面光潔度，但是是有一些問題的領(lǐng)域。另一種非常規(guī)加工過程是超聲波鉆探，現(xiàn)在廣泛使用于兩種導(dǎo)電和非金屬材料。最好是低延展性（科瓦爾Chemo1986;克雷默等1988;莫爾蘭，1988年）和硬度上述40HRC（維爾馬等。，2003; Downfield等。，1999;Ezugwa and Wang，1997年;吉爾摩，1990年），例如：無機(jī)玻璃，氮化硅等（Theo等。，1998; IMS的，2002年;康巴和辛格Repined，2003年本篤加里，1987年; Hazlehurst，1981年;彭特蘭和Entertains，1965）。在這個過程中工具用堅韌的材料制成，在該命令的頻率振蕩Keck的20-30 / s的幅度約可達(dá)0.02mm。一種磨料填補沖洗液通過主機(jī)和工件之間的差距。
這種材料的去除機(jī)理涉及到侵蝕和研磨（本篤加里，1987年）。固定超聲波鉆孔的原則如圖1，微小的磨料切下小薄片和研磨的面對應(yīng)。IMF材料不壓縮，扭曲或加熱，因為磨削力很少超過2磅（IMS的，2002年）。對于加工聯(lián)系中沒有未有任何工具，冷漿的存在使這是一個寒冷的切割過程。
加工所用的工具經(jīng)過銀釬焊工藝處理過。（辛格，2002年）。給予該工具的振動的振幅也影響切削率（康巴和辛格Repined，2003年）。人們已經(jīng)發(fā)現(xiàn)，該材料去除率受振蕩幅度，磨料大小的影響（辛格，2002年;辛格和康巴，2007年）。有大量超聲波鉆孔的應(yīng)用，包括從在氧化鋁基板制造小孔，以雕刻玻璃器皿，通過激光板鉆大孔（IMS ，2002年）。圖2顯示了超聲鉆削應(yīng)用于一個超磁致伸縮換能器或壓電與釬焊和螺紋工具的三維視圖。據(jù)觀察實驗發(fā)現(xiàn)，用氧化鋁作為漿料，TITAN15 作為工程材料，材料去除速率先減小，在增加額定功率（從150W至300W），超聲波打孔機(jī)（超聲波電機(jī)）的增幅從以約300W 增至450W。（辛格和康巴，2003年）
圖。 1 - 超聲波鉆孔示意圖，?噸=滲透到工具，?瓦特=滲透到工件
圖 2 三維超聲波電機(jī)圖案
在目前的實驗裝置中，振幅的典型值和振動頻率的使用是0.0253 -0.0258毫米和20千赫± 200赫茲。這一實驗曾進(jìn)行研究，其目的是了解材料去除率和刀具磨損率。比較TITAN15和TITAN31（有不同的組合，不同的韌性）鉆孔超聲，3種不同類型的泥漿，即碳化硅（Sic），硼碳化物（碳化硼）和氧化鋁（Al2O3）（每320粒度）。極限拉伸強度為491MPa的純鈦TITAN15（化學(xué)分析中：C，0.006％;小時，0.0007％，氮，0.014％;澳，0.140％;，0.05％鐵;鈦平衡）和極限拉伸強度為994MPa的鈦合金TITAN31（化學(xué)分析：?，0.019％;，0.0011％，H組，氮，0.007％，澳，0.138％，鋁，6.27％;五，4.04％;鐵，0.05％，鈦，平衡）。
在執(zhí)行500W的聲波加工，超聲鉆探機(jī)在三個不同的額定功率（即在150瓦，300瓦和450瓦），的試點上的做基礎(chǔ)實驗。三種常規(guī)刀具材料，即不銹鋼（SS），鈦（Ti）和高速鋼（HSS）被用作鈦工具組合，以找出材料移除率和刀具磨損率，在修復(fù)泥漿濃度和溫度。漿料濃度定為15％。?為25.7％和漿料溫度（室溫）。圖 3顯示工件尺寸，該工具被認(rèn)為決定維持經(jīng)濟(jì)加工操作的空形狀極限。
2實驗
實驗已經(jīng)進(jìn)行了6次調(diào)校，以確定影響
圖3 工件的詳細(xì)圖紙。
關(guān)于TITAN15的不銹鋼工具在蒸餾水含量為15%,使用粒度為320的氧化鋁泥漿的情況。該實驗開始時設(shè)置機(jī)械應(yīng)力率的評分為超聲波打孔機(jī)的（30％為500W）150W。然后，允許機(jī)器鉆具有常不斷泥漿流速和泥漿溫度的固定深度為1mm。備受關(guān)注的深度利用千分表觀察。相應(yīng)地，采取超聲波電機(jī)鉆探所需時間用秒表測量。加工完成后，為尋找不同重量的損失，工件和刀具體重被測量。
相應(yīng)的材料去除率和刀具磨損率在功率為150W，300W和450W（500瓦的30％，60％和90％）時進(jìn)行了計算。在第一個設(shè)備的兩個實驗，設(shè)置使用碳化硼漿料，碳化硅泥漿TITAN15工具工件。圖 5顯示降低死亡率和TITAN15的推理-重量比趨勢，在不同機(jī)器使用功率等級。第二個設(shè)備包括TITAN31工件在三個超聲功率設(shè)置的加工。
圖4 幾何工具的詳細(xì)圖紙（辛格and Kaman，2007年）
圖 5 材料去除率和推理-重力比使用額定功率（W / P的TITAN15and工具SS）的。
圖 6 材料去除率和推理-重力比使用額定功率（W / P的TITAN31and工具SS）的。
圖 7 材料去除率和推力-重力比使用額定功率（W / P的TITAN15and工具鈦）。
3。結(jié)果和討論
在六個不同的設(shè)備進(jìn)行重復(fù)數(shù)量的實驗調(diào)校，比較結(jié)果已經(jīng)繪制。從圖5可以觀察整體TITAN15的材料去除率比使用氧化鋁漿料不銹鋼工具的推理-重量比整體較低，。然而第一組的三個實驗材料去除率的趨勢相似。隨著機(jī)器額定功率的增加，由于較高的功率值磨料產(chǎn)生更多勢頭，隨著機(jī)器相當(dāng)高的功率值的增加，材料去除率的增加是相當(dāng)明顯的。因此，更多工件的侵蝕，但在某些情況下，隨著額定功率的增加，材料去除率的增加，這可能是因為降低了工作件的應(yīng)變硬化。隨著MRR的增加，刀具的磨損率也在提高。
圖 8 材料去除率和推力-重力比使用額定功率（W / P的TITAN31和工具鈦）。
圖9 材料去除率和推力-重力比使用額定功率（W / P的TITAN15and工具高速鋼）
圖 10 材料去除率和推力-重力比使用額定功率（W/PTITAN31高速鋼和工具）。
但是有時推力-重力比隨著額定功率在MRR方面的增加或降低，額定功率是很明顯的。這種現(xiàn)象的原因還有工具表面的應(yīng)變硬化。漿料類型的選擇對TITAN15的材料去除率，在這種情況下作為不重要的因素。然而，獲得更好的工具性能與氧化鋁漿料才是重要的。
至于對TITAN31不銹鋼工具的加工，材料去除率和推力-重力比的趨勢與TITAN31不銹鋼工具以前的情況是不同的。（指圖6）。這變化的原因可能是工件/刀具材料在特定的超聲功率基于其材料/化學(xué)成分特征的應(yīng)變硬化。TITAN31不銹鋼工具的加工的最好的參數(shù)在碳化硼漿料300W時已被觀察。
圖11機(jī)加工，展示了傳統(tǒng)的機(jī)械加工和表面顯微照片對比超聲加工;倍率：100×。超聲波
加工表面（鐳0.46），常規(guī)機(jī)加工表面（鐳0.8）。
在接下來設(shè)備，當(dāng)鈦的工具的設(shè)置使用，而已被發(fā)現(xiàn)。TITAN15的材料去除率，材料去除率表明泥漿類型的影響是微不足道的，其中作為TITAN31的選擇已經(jīng)被證明是重要因素。最好的設(shè)置已達(dá)到對于TITAN31是300W時的泥漿與碳化硼。
與'第五和第六設(shè)置突出了高速鋼工具'對于TITAN15和ITAN31工件的加工。這一趨勢得到，材料去除率和推力-重力比在第五和第六對碳化硼為Al2O3和泥漿的調(diào)校，幾乎是相似的，但碳化硅一些變化已經(jīng)觀察到。碳化硼漿料全部證明了是最好的選擇。這可能是因為基于相對硬度的工具和工件更好的特定加工條件。
圖11顯示了一個表面超聲加工鈦樣品展現(xiàn)了當(dāng)和一傳統(tǒng)加工的面比較時，非定向的表面紋理。由超聲波產(chǎn)生加工，這些細(xì)化晶粒結(jié)構(gòu)可以擁有更好地強度和機(jī)械性能。（辛格和康巴，2006年，2007年Judean等。，2006年）。
4。結(jié)論
從實驗中可以得出以下結(jié)論：
1。鈦是利用超聲波鉆探可一很好加工。如果工件高韌性值的工件是加工，并非總是必要的，MRR值將會減少。相反，它是相對工具和工件混合材料的組合影響。通過使用特定的工具可以達(dá)到較低的推力-重力比和更好的材料去除率。在特定工件的額定功率值和控制實驗條件如泥漿類型的條件下。
2。使用不銹鋼工具和碳化硼泥漿已經(jīng)獲得最好的結(jié)果。在這些實驗中獲得的這些結(jié)果表明在不同情況下具有密切的關(guān)系。（辛格，康巴，2007年b）。
3。不銹鋼，鈦和高速鋼工具沒有遇到重大疲勞的問題，，任和碎片或折斷通常是由于刀具/孔在制造過程中錯位造成的。
4。驗證實驗顯示，在一般情況下，在材料去除率方面對于所選定工件（TITAN15和TITAN31）。有34.46％的改善。
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journal of materials processing technology 197 (2008) 200–205 journal homepage: Comparison of slurry effect on machining asonic drilling , Ludhiana 28 May 2007 Accepted 1 June 2007 eviews carbide same quently presented on the production of 5mm diameter holes in pure titanium (TITAN15, ASTM Gr2) and titanium alloy (TITAN31, ASTM Gr.5) using ultrasonic drilling. This entailed the use of a 20kHz piezoelectric transducer with three solid tools of stainless steel, titanium and high-speed steel, operating in silicon carbide, boron carbide and alumina slurry. The data presented includes main effect plots for material removal rate and tool wear rate. The Keywords: Ultrasonic drilling Material removal rate Tool wear rate Silicon carbide Boron carbide Alumina Stainless steel Titanium High speed steel results suggested that boron carbide slurry and stainless steel tool was giving best material removal rate. Also relative hardness of tool–work piece affects the material removal rate in ultrasonic machining. ? 2007 Elsevier B.V. All rights reserved. 1. Introduction Titanium alloys are generally regarded as been amongst the most difficult of work piece materials to machine in spite of their relatively low hardness (e.g. Ti 6/4 annealed ～350HV). This is due to their low thermal conductivity, which con- centrates heat in the cutting zone (Ti 6/4 has a thermal conductivity of 11W/mK for AISI 405 steel), high chemical reactivity at elevated temperature and a tendency to form localized shear bands. Titanium and its alloys are branded as difficult to machine materials (Verma et al., 2003). Unfortu- nately, the machining of titanium is in general more difficult and consequently a significant proportion of production costs ? Corresponding author. E-mail address: rupindersingh78@ (R. Singh). may relate to machining, even though only small volumes of material may be removed. Titanium and its alloys are very popular and are very widely used in aerospace, marine gas turbine engines and surgical applications. Poor thermal con- ductivity of titanium alloys retard the dissipation of heat generated, creating, instead a very high temperature at the tool–work piece interface and adversely affecting the tool life (Dornfeld et al., 1999). Titanium is chemically reactive at elevated temperature and therefore the tool material either rapidly dissolves or chemically reacts during the machin- ing process resulting in chipping and premature tool failure (Verma et al., 2003). Compounding of these characteristics is the low elastic modulus of titanium, which permits greater 0924-0136/$ – see front matter ? 2007 Elsevier B.V. All rights reserved. doi:10.1016/j.jmatprotec.2007.06.026 characteristics of titanium in ultr R. Singh a,? , J.S. Khamba b a Mechanical preferably those with low ductility (Koval Chenko et al., 1986; Kremer et al., 1988; Moreland, 1988) and hard- ness above 40HRC (Verma et al., 2003; Dornfeld et al., 1999; Ezugwa and Wang, 1997; Gilmore, 1990), e.g. inorganic glasses, silicon nitride, etc. (Thoe et al., 1998; IMS, 2002; Khamba and Singh Rupinder, 2003; Benedict Gary, 1987; Haslehurst, 1981; Pentland and Ektermanis, 1965). In this process tool is made of tough material, oscillated at frequencies of the order of 20–30Kc/s with amplitude of about 0.02mm. An abrasive filled fluid flushed through the gap between master and work piece. The material removal mechanism involves both erosion and grinding (Benedict Gary, 1987). The principle of stationary ultrasonic drilling has been shown in Fig. 1.The tiny abrasive c The the an this v g Singh r ab n fa glass 2002 drilling ducer e material, in 300 and F ? Three conventional tool materials namely stainless steel (SS), titanium (Ti) and high-speed steel (HSS) have been used as tool combinations with titanium as work material to find out material removal rate (MRRs) and tool wear rate (TWR) at fix slurry concentration and temperature. The slurry concentra- tion was fixed at 15vol.% and slurry temperature at 25.7 ? C (room temperature). An experimental set-up having a provi- sion for variation in the process parameters was designed and fabricated. Fig. 3 shows work piece dimensions. The dimen- sions of the tool were decided keeping in view the limitations of the ‘horn shape’ to economize the machining operation (Fig. 4). 2. Experimentation The experiments have been conducted in six set-ups. In the firstset-up,experimentwasperformedtodeterminetheeffect hip off microscopic flakes and grinds a counterpart of face. work material is not stressed, distorted or heated because grinding force is seldom over 2lb (IMS, 2002). There is never y tool to work contact, and presence of cool slurry makes a cold cutting-process. The tool used for machining has been prepared by sil- er brazing process (Singh, 2002). The amplitude of vibrations iven to the tool also influences the cutting rate (Khamba and Rupinder, 2003). It has been found that the material emoval rate is affected by amplitude of oscillations, size of rasive (Singh, 2002; Singh and Khamba, 2007a). There are umber of applications of ultrasonic drilling, ranging from the brication of small holes in alumina substrates, to engraving ware, to drilling large holes through laser blocks (IMS, ). Fig. 2 shows the three-dimensional view of ultrasonic using either a magnetostrictive or piezoelectric trans- with brazed and screwed tooling. It has been observed in xperimentationusingaluminaasslurryandTITAN15aswork materialremovalratefirstdecreaseswithinincrease power rating (from 150W to 300W) and than increases from W to 450W of ultrasonic drilling machine (USM) (Khamba Singh Rupinder, 2003). ig. 1 – Schematic diagram of ultrasonic drilling, t=penetration in to tool, ?w=penetration in to work piece. Fig. 2 – Three-dimensional pictorial view of USM. In the present experimental set-up the typical value of amplitude and frequency of vibration used were 0.0253–0.0258mm and 20kHz±200Hz. This experimental study has been conducted with the objective to understand material removal rate and tool wear rate comparison of TITAN15 and TITAN31 (having different composition, dif- ferent toughness) when drilled ultrasonically; with three different types of slurries, namely silicon carbide (SiC), boron carbide (B 4 C), and alumina (Al 2 O 3 ) (each of 320 grit size). The pure titanium TITAN15, has ultimate tensile strength of 491MPa (chemical analysis: C, 0.006%; H, 0.0007%; N, 0.014%; O, 0.140%; Fe, 0.05%; Ti, balance) and titanium alloy TITAN31, has ultimate tensile strength of 994MPa (chemical analysis: C, 0.019%; H, 0.0011%; N, 0.007%; O, 0.138%; Al, 6.27%; V, 4.04%; Fe, 0.05%; Ti, balance). The machining was performed on 500W Sonic-Mill, ultra- sonic drilling machine at three different power ratings (i.e. at 150W, 300W and 450W), based upon pilot experimentation. 202 journal of materials processing technology 197 (2008) 200–205 Fig. 3 – Detailed drawing of the work piece. on ‘TITAN15 of SS tool’ using alumina slurry of 320 grit size; at 15% concentration in distilled water as suspension media. The experiment started by setting power rating of the machine at (30% of 500W) 150W of ultrasonic drilling machine. The ini- tial weight of titanium work piece ‘that is of TITAN15’ and tool ‘that is of SS’ was measured. Then machine was allowed to drill for fixed depth of 1mm with constant slurry flow rate Fig. 5 – MRR and TWR vs. power rating using (W/P TITAN15 and tool SS). Fig. 6 – MRR and TWR vs. power rating using (W/P TITAN31 and tool SS). and slurry temperature. The depth was closely watched using dial gauge. Correspondingly, time taken by USM for drilling was measured using stopwatch. After machining was com- pleted, work piece and tool weight was measured for finding difference in weight loss. Corresponding material removal rate and tool wear rate were calculated at 150W, 300W, and 450W (30%, 60% and 90% of 500W). In the first set-up two more experiments were set using ‘TITAN15 work piece SS tool’ with B 4 C slurry and SiC slurry, respectively. Fig. 5 shows the trend of MRR and TWR of TITAN15 work material with SS tool at different power rating of machine used. The second set-up involved machining of ‘TITAN31 work piece by SS tool’ at three settings of ultrasonic power rating Fig. 4 – Detailed drawing of the tool geometry (Singh and Khamba, 2007a,b). with Al 2 O 3 ,B 4 C and SiC slurry. Corresponding MRR and TWR were plotted (refer Fig. 6). The third and fourth set-up covered machining of ‘TITAN15 and TITAN31 work piece by Ti tool’ at three settings of ultrasonic power rating with Al 2 O 3 ,B 4 C and SiC slurry. Corresponding MRR and TWR were plotted (refer Figs. 7 and 8). In the fifth and sixth set-up machining of ‘TITAN15 and TITAN31 work piece by HSS tool’ at three settings of ultra- sonic power rating with Al 2 O 3 ,B 4 C and SiC slurry has been performed. Corresponding MRR and TWR were plotted (refer Figs. 9 and 10). journal of materials processing technology 197 (2008) 200–205 203 Fig. 7 – MRR and TWR vs. power rating using (W/P TITAN15 and tool Ti). 3. Results and discussion From repetitive number of experiments conducted under six different set-ups, the comparative results have been plotted. From Fig.5,ithasbeenobservedthatMRRofTITAN15isoverall lo e similar mac r kinetic piece decr piece F and and tool HSS). Fig. 10 – MRR and TWR vs. power rating using (W/P TITAN31 and tool HSS). wer than TWR while using SS tool with Al 2 O 3 slurry. How- ver trend for MRR in all three experiments of first set-up were . The increase of MRR with increase in power rating of hine is quite obvious because of higher value of power ating abrasive particles strikes with more momentum and energy with work piece. Hence more erosion of work but in certain cases, with increase in power rating, MRR eases which may be because of strain hardening of work . The increase of tool wear rate with increase in MRR and ig. 8 – MRR and TWR vs. power rating using (W/P TITAN31 tool Ti). Fig. 9 – MRR and TWR vs. power rating using (W/P TITAN15 power rating is quite obvious but sometimes TWR decreases withpowerratingincrease/increaseinMRR;thereasonforthis isagainstrainhardeningoftoolsurface.Theselectionofslurry type for MRR of ‘TITAN15’ in this case comes out as unimpor- tant factor. However better tool properties were obtained with Al 2 O 3 slurry. As regards to machining of ‘TITAN31 with SS tool’ the trend for MRR and TWR were different from previous case of ‘TITAN15 with SS tool’ (refer Fig. 6). The main reason for this variation may be strain hardening of work piece/tool material at specific ultrasonic power rating based upon its mate- rial/chemical composition characteristics. The best parameter setting for machining of ‘TITAN31 with SS tool’ has been observed at 300W with B 4 C slurry. 204 journal of materials processing technology 197 (2008) 200–205 compar (Ra references Fig. 11 – Photomicrograph of the machined surface showing machining; magnification: 100×. Ultrasonic machined surface In the next set-up while using titanium tool it has been found that for ‘TITAN15’; MRR showed insignificant effect of slurry type, where as for ‘TITAN31’ choice of slurry has come out as important factor. The best settings have been attained with B 4 C slurry at 300W for ‘TITAN31’. The fifth and sixth set-up highlighted machining with ‘HSS tool’ for ‘TITAN15 and ITAN31’ work piece. The trend obtained for MRR and TWR in fifth and sixth set-ups is almost similar for Al 2 O 3 and B 4 C slurry, but for SiC some variation has been observed. Overall B 4 C slurry comes out as better option. This may be because of better work piece and tool combinations based on relative hardness of tool and work piece for specific machining conditions. Fig. 11 shows the surface of an ultrasonically machined titanium sample exhibits a non-directional surface texture when compared with a conventionally machined (ground) sur- face. These refined grain structure, resulting from ultrasonic machining, can give better strength and mechanical proper- ties. The results agree with experimental observations made otherwise (Singh and Khamba, 2006, 2007b; Jadoun et al., 2006). 4. Conclusions From the experiment following conclusions can be drawn: 1. Titanium is well machinable using ultrasonic drilling machine. It is not always necessary that if work piece with higher toughness value is machined, it will have less MRR rather it is combination effect of material composition (hardness of work piece) relative of tool and work piece. Less TWR and better MRR can be attained by using spe- cific tool, work piece combination at specific power rating values and controlled experimental conditions like slurry type. 2. Best results have been obtained with SS tool and boron car- bide slurry. These results show close relationship between the experimental observations made otherwise (Singh and Khamba, 2007b). 3. No major fatigue problems were encountered with the stainless steel, titanium and high-speed steel tool, any chipping/fracture generally being due to tool/hole mis- alignment during fabrication. ison of the conventional machining and ultrasonic 0.46), conventionally machined surface (Ra 0.8). 4. The verification experiments revealed that on an average there was 34.46% improvement in MRR, for the selected work piece (TITAN15 and TITAN31). Benedict Gary, F., 1987. Non Traditional Manufacturing Processes. Marcel Dekker, Inc, pp. 67–86. Dornfeld, D.A., Kim, J.S., Dechow, H., Hewsow, J., Chen, L.J., 1999. Drilling burr formation in titanium alloy Ti–6Al–4V. Ann. CIRP 48, 73–76. Ezugwa, E.O., Wang, Z.M., 1997. Titanium alloys and their machinability—a review. J. Mater. Process. Technol. 68, 262–274. Gilmore, R., 1990. Ultrasonic Machining of Ceramics, SME Paper MS 90-346, p. 12. Haslehurst, M., 1981. Manufacturing Technology, 3rd ed. Arnold, Australia, pp. 270–271. Instruction Manual for Stationary SONIC-MILL 500 W Model, 2002. Sonic-Mill, USA. Jadoun, R.S., Kumar, P., Mishra, B.K., Mehta, R.C.S., 2006. Ultrasonic machining of titanium and its alloys: a review. Int. J. Mach. Mach. Mater. 1 (1), 94–114. Khamba, J., Singh Rupinder, S., 2003. Effect of alumina (white fused) slurry in ultrasonic assisted drilling of titanium alloys (TITAN 15). In: Proceedings of the National Conference on Materials and Related Technologies (NCMRT), pp. 75–79. Koval Chenko, M.S., Paustovskii, A.V., Perevyazko, V.A., 1986. Influence of properties of abrasive materials on the effectiveness of ultrasonic machining of ceramics. Sov. Powder Metall. Metal Ceram. 25, 560–562. Kremer, D., Mackie, J., Ultrasonic, 1988. Machining applied to ceramic materials. Ind. Ceram. 830, 632–637. Moreland, M.A., 1988. Versatile performance of ultrasonic machining. Ceram. Bull. 6, 1045–1047. Pentland, E.W., Ektermanis, J.A., 1965. 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