Journal of Materials Processing Technology

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1 Journal of Materials Processing Technology 229 (2016) Contents lists available at ScienceDirect Journal of Materials Processing Technology jo ur nal home p ag e: Increase in ironing limit of aluminium alloy cups with lubricants containing nanoparticles C.J. Tan a,b,, Y. Abe c, W. Daodon c, N. Takahashi c, K. Mori c, J. Purbolaksono a,b a Department of Mechanical Engineering, Faculty of Engineering, University of Malaya, Kuala Lumpur, Malaysia b Centre of Advanced Manufacturing and Material Processing (AMMP Centre), Level 8, Engineering Tower, Faculty of Engineering, University of Malaya, Kuala Lumpur, Malaysia c Department of Mechanical Engineering, Toyohashi University of Technology, Toyohashi, Aichi , Japan a r t i c l e i n f o Article history: Received 27 July 2015 Received in revised form 29 October 2015 Accepted 30 October 2015 Available online 5 November 2015 Keywords: Ironing Deep drawing Seizure Nanotechnology Aluminium alloys Tribology a b s t r a c t The seizure resistance in the ironing process of aluminium alloy cups was improved with lubricants containing SiO 2 nanoparticles, and the ironing limit of the cups was increased. The effects of suspending different concentrations of SiO 2 particles in sulfur based mineral oils at three viscosity levels on increasing the ironing limit of Al 3003-O cylindrical cups before seizure were investigated using a lapped TiCN cermet die under a near production rate of 100 mm/s. By suspending a mere 1.0 wt% of SiO 2 in oil with a kinematic viscosity of 170 mm 2 /s, the ironing limit of the cup was increased from 24.8% to 35.2%. The ironing limit was slightly reduced to 34.8% when the viscosity level was excessive i.e., 500 mm 2 /s with 1.0 wt% of SiO 2. When the viscosity level was too high, the ironing load increased and the seizure resistance was slightly reduced. However, the amount of increase for the low viscosity oil was only 27.5% with 5.0 wt% of SiO 2. When the viscosity was too low, the film thickness at the contact surface was less than the average surface roughness, leading to direct contact between the asperities. Hence, a large amount of SiO 2 was required to prevent seizure. The surface roughness of the ironed cups remained unchanged with the presence of the nanoparticles in the lubricant. By increasing the ironing limit, lightweight cups with a smooth surface, thin wall thickness and elongated height were successfully formed in the experiment. The seizure resistance of the ironing die was also improved with the medium and high viscosity oils containing nanoparticles for obtaining high ironing ratios Elsevier B.V. All rights reserved. 1. Introduction The deep drawing and ironing process is widely employed to form battery containers for electric or hybrid vehicles (Kuno et al., 2011), kitchen utensils, beverage can bodies and other auto parts from aluminium alloy or stainless steel sheets due to its high productivity and the reduced material waste involved. In this process, the sheets are first drawn deeply into cylindrical or rectangular cups having barrel-shaped side walls. The pre-drawn cups are then pushed through an ironing die or ring with a small die clearance to obtain straight side wall having uniform thickness, elongated height and improved surface roughness. Since the side wall thickness of the pre-drawn cup constantly increases from the corner to the mouth area (Odell, 1978), the amount of ironing increases with Corresponding author at: Department of Mechanical Engineering, Faculty of Engineering, University of Malaya, Kuala Lumpur, Malaysia. Fax: addresses: tancj1@yahoo.com, tancj@um.edu.my (C.J. Tan). cup height, resulting in severe seizure in the axial direction around the mouth area if no proper lubrication is applied. The maximum reduction in side wall thickness is often limited by seizures on the cup surface due to the high frictional force acting at the sliding surfaces. Under extreme contact pressure, localized bonding is formed between the asperities of the two contacting surfaces. The asperity roots of the softer side are torn apart under the sliding motion leading to the formation of the seizure. Abe et al. (2013) increased the ironing limit of stainless steel and aluminium alloy drawn cups with a TiCN-based cermet die which had micro pockets on its surface for trapping lubricants. Good lubrication helped reduce the ironing load due to a decrease in the frictional force at the contact surface. Moshksar and Kalvarzi (2001) reported that the ironing load for aluminum alloy cups decreased when the viscosity of the lubricant was increased. Katsuhiro and Masao (1976) increased the ironing speed and reduced the ironing load by irradiating ultrasonic waves toward the pre-drawn cup. Tan et al. (2013) minimized the ironing load in a box-shaped end forming process with a tapered square punch and a tapered square die. The resistance to seizure can / 2015 Elsevier B.V. All rights reserved.

2 C.J. Tan et al. / Journal of Materials Processing Technology 229 (2016) Table 1 Mechanical properties of A3003-O aluminum alloy. Ultimate tensile strength (MPa) Total elongation (%) n-value r-value Hardness (HV5) Surface roughness, R a ( m) Table 2 Diameters of punch and die in the forming of pre-drawn cups for different ironing ratios. Nominal ironing Diameter of ratio r n drawing punch,d p (mm) Diameter of drawing die, d d (mm) Fig. 1. Mechanism for increase in seizure resistance in ironing process. be increased by adding solid additives such as molybdenum disulfide (Yamashita and Goto, 2005) and graphite (Hosoe et al., 1998) with a lamellar structure in dry powder form. In the direction of the motion, the lamellas easily shear over each other resulting in low friction. Chlorinated Paraffins are widely added in stamping lubricants as Extreme Pressure (EP) additives to prevent adhesive wear for low cost and versatile applications. However, chlorinated paraffin is not perceived to be environmentally friendly due to it being persistent, bioaccumulative, and toxic to aquatic organisms even at low concentrations. Kim et al. (2007) evaluated various dry film solid lubricants using deep drawing tests with increased blank holding force. Dry film lubricants performed better than oil-based lubricants in the tests. Kim and Altan (2009) reported that polymeric lubricants containing EP additives performed better than water emulsion and straight oil lubricants in deep drawing and ironing tests. Nanoparticles such as SiO 2 are sphere-like in shape, are chemically stable, and have high temperature resistance and low cost. They have been widely used as additives to improve the tribology performance of some lubricants in load-bearing processes such as metal cutting (Sarhan et al., 2012), and sliding bearing (Sia et al., 2014). The reduction in the amount of wear (Ito et al., 2006; Jiao et al., 2011) and the increase in resistance to seizure (Kobayashi et al., 2004; Hosoe et al., 1997) from SiO 2 have been reported in various tribo tests. Yanagihara et al. (2003) reported that the rolling motion of the nanoparticles in the metal cutting process prevented direct contact between the cutting chips and the tool. Hence, the chip flow was facilitated and the resistance to seizure of the tool was increased. However, the application of lubricants containing nanoparticles in the sheet metal forming processes, particularly in the ironing process, has yet to be reported. In this study, the effect of a quantity of SiO 2 suspended in sulfur based mineral oils having different viscosity levels on increasing the seizure resistance of Al 3003-O ironed cups was investigated using a lapped TiCN cermet ironing die under a near production speed of 100 mm/s. Fig. 2. Conditions for deep drawing process. Fig. 3. Ironing conditions for pre-drawn cups. 2. Mechanism for increase in seizure resistance with a lubricant containing SiO 2 In the ironing process, the side wall thickness of a pre-drawn cup is reduced with a die clearance smaller than the initial blank thickness. During ironing, the side wall is subject to high contact pressure. The asperities of both the tool and the blank surfaces are in direct contact when the film thickness of the lubricant is smaller than the average surface roughness or when conditions are dry, as shown in Fig. 1(a). Cold bonding tends to form between asperities under the high pressure, with stress being greatest at the asperity roots of some of the cracks in the material. The continuous fragmentations of the asperity roots along the cup surface during the process forms the seizure, and wear fragments are produced. For oils with medium and above viscosity, the film thickness is larger than the average surface roughness as shown in Fig. 1(b). Since the cup is pushed axially into the ironing die and the nanoparticles are sandwiched between the cup and the die surfaces under high compression, the relative motion of the nanoparticles is confined in the axial direction. The asperities are smoothened by the relative

3 806 C.J. Tan et al. / Journal of Materials Processing Technology 229 (2016) Fig. 4. Photo and dimensions of TiCN-based cermet ironing die. Fig. 5. Surface profile in the axial direction of lapped TiCN-based cermet die. Table 3 Material properties of SiO 2 nanoparticles. Structure Amorphous Melting point ( C) Approx Average size (nm) 5 15 Hardness (HV) 1000 Density (g/cm3) 2.2 Thermal conductivity at 300 K (W/cm K ) Table 4 Vickers hardness for A3003-O blank, SiO 2 and ironing die. A3003-O SiO 2 Ironing die Hardness/HV motions of the nanoparticles, and the formation of local bonding is prevented, resulting in high seizure resistance. When the ironing ratio has exceeded its limit, the full penetration of the nanoparticles into the cup surface under extreme pressure leads to the formation of seizure due to the direct contact between the asperities at the interface. 3. Experimental conditions for deep drawing and ironing process A3003-O circular blanks measuring 66 mm in diameter and 0.6 mm in initial blank thickness were used in the experiment. The diameter of the blank was obtained from its limiting drawing ratio. The mechanical properties of A3003-O aluminum alloy are shown in Table 1. Prior to the ironing process, the circular blanks were first drawn into cylindrical cups under a constant blank holding force of 1 kn. The deep drawing conditions are shown in Fig. 2. The diameters of the punch and the die in the forming of pre-drawn cups for different ironing ratios are shown in Table 2. The diameters of the ironing and drawing punches were set to the same value to allow the insertion of the ironing punch into the pre-drawn cup prior to the ironing process. Since the diameter of the ironing punch was increased for a high ironing ratio, the diameters of the drawing punch and drawing die were increased as well. The clearance, c between the drawing punch and the drawing die was set equal to the sheet thickness i.e. 0.6 mm in all cases. A small amount of ironing has taken place around the side walls of the cups in the drawing process due to thickness increase in the flange. However, this amount is not significant in comparison to the target ironing ratios. The process was performed with a 250 kn universal tensile testing machine under a constant speed of 8.3 mm/s. A lubricant with a kinematic viscosity of 562 mm 2 /s was applied to the die and the blank holder only, while the punch was kept dry during the drawing process. The ironing conditions for the pre-drawn cups are shown in Fig. 3. The inner diameter of the ironing die was fixed at 34 mm, while the diameter of the punch, dp was varied to obtain different ironing ratios ranging from 10 to 50%. The nominal and real ironing ratios were calculated based on the following formulas. The real ironing ratio was slightly smaller than the nominal one due to elastic deformation of the die and thickness variation in the circumference direction of the cup. r n = t 0 c x100% (1) t 0 r r = t 0 t 1 x100% (2) t 0 where, r n = nominalironingratio r r = realironingratio t 0 = initialblankthickness

4 C.J. Tan et al. / Journal of Materials Processing Technology 229 (2016) Fig. 6. Photos of ironed cups for different concentrations of SiO 2 suspended in lubricant VG10. Fig. 7. Real ironing ratios of cup and photos of die surface for different concentrations of SiO 2 suspended in lubricant VG10.

5 808 C.J. Tan et al. / Journal of Materials Processing Technology 229 (2016) Fig. 8. Photos of ironed A3003-O cylindrical cups for different concentrations of SiO 2 suspended in lubricant VG170. Table 5 Kinematic viscosities of lubricants. Lubricant Kinematic viscosity (@ 40 C), v (mm 2 /s) G-3744H 562 VG10 10 VG VG c = clearancebetweenpunchanddie t 1 = measuredaveragesidewallthicknessafterironing In the ironing process, the cup was first inserted into the punch. Both the punch and cup were then pushed through the ironing die with a 800 kn servo press under a constant speed of 100 mm/s. SiO 2 particles were added to three types of sulfur based mineral oils containing paraffin, namely VG10, VG170 and VG500, having viscosities of 10 mm 2 /s, 170 mm 2 /s and 500 mm 2 /s, respectively, at different concentrations ranging from w = 0 5 wt% (or equivalent to 0 2 vol%). The mixture of lubricant was applied to the side wall of the cup and the ironing die only, while the punch was kept dry. The SiO 2 particles were uniformly dispersed in the oil by the sonification process using an ultrasonic cleaning machine. The mixtures of particles and oils were continuously vibrated for six hours to avoid agglomeration of the particles. The lapped ironing die was made of TiCN-based cermet with an average surface roughness of 0.02 mra. The material properties of SiO 2 are shown in Table 3. The average sizes of the particles were 5 15 nm. The Vickers hardness of the particle was 1000HV. It had a high melting point of 1600 C and low thermal conductivity. The ironing tests, particularly at the maximum ironing ratios were performed two times to prevent the scatter of results. The Vickers hardness for the A3003-O blank, SiO 2 particles and ironing die are shown in Table 4. The Vickers hardness of SiO 2 and the ironing die are approximately 4 and 6.5 times that of the blank. Hence, a seizure was formed at the cup surface. Table 6 Mechanical properties and surface roughness of lapped TiCN-based cermet die. Die material R z ( m) R a ( m) Elastic modulus (GPa) Hardness (HV50) TICN cermet The kinematic viscosities of lubricants used in the deep drawing and ironing process are shown in Table 5. Pre-drawn cups were formed with the lubricant G-3744H only. Other lubricants were used in the ironing process. The photo and the dimensions of the TiCN-based cermet ironing die are shown in Fig. 4. The TiCN-based cermet ironing die was inserted into a holder. The holder was made of carbon steel SNCM447. The inner diameter of the die was fixed at 34 mm and the height of the die land was 1 mm. The cermet was formed using the pressureless sintering process. Chromium nickel alloy steel powders were added into the titanium carbonitride as sintering additive. Cermet composite was formed after the sintering process. The mechanical properties and the surface roughness of the lapped TiCN-based cermet die are shown in Table 6. The die surface was lapped with fine diamond particles to obtain smooth surfaces. The surface profile in the axial direction of the lapped die is shown in Fig. 5. After lapping, the die surface had an average surface roughness, Ra = 0.01 m. The die surface was finely polished to facilitate the relative motions of the SiO 2 particles in the contacting zone. 4. Effect of lubricants containing SiO 2 on the ironing process of cylindrical cups 4.1. Ironing limits for lubricant VG10 The photos of ironed cups having a seizure or smooth surface for different concentrations of SiO 2 suspended in the lubricant VG10 are shown in Fig. 6. The real ironing ratio for the first seizure slowly increased from 23.4% to 29.0% when the concentration of the SiO 2, w was increased from 0.1 wt% to 1.0 wt%. However, the ratio slightly decreased to 25.9% for w = 2.0 wt%. A cup having a smooth surface

6 C.J. Tan et al. / Journal of Materials Processing Technology 229 (2016) was successfully obtained at real ironing limit of 27.5% for w = 5 wt%. The ironing limit for w = 5 wt% was only 2.7% higher than the one obtained with plain oil. The ironing limit of the cup was slightly increased by suspending a very high concentration of SiO 2 in a low viscosity lubricant. The real ironing ratios of cup, r r and the photos of the die surface for different concentrations of SiO 2 are shown in Fig. 7. SiO 2 had very little effect on increasing the ironing limit of the cups and the seizure resistance of the ironing die surface when the viscosity of the lubricant was low. The ironing limit was only slightly increased for a high concentration of SiO 2. Besides the cup surfaces, seizures were also observed at the die surfaces for w = 0.0 wt% to 2.0 wt% when the ironing limits were exceeded. The average ironing limit of the cups for w = 5.0 wt% was slightly reduced to 27.0% due to the scatter of the results Ironing limits for lubricant VG170 The photos of the ironed cups having a seizure or smooth surface for different concentrations of SiO 2 suspended in the lubricant VG170 are shown in Fig. 8. Although seizures were observed when r r = 26.8% and 33.8% for w = 0 wt% and w = 0.5 wt%, the ironing ratios for cups having a smooth surface were increased to 35.2% and 34.0%, respectively, for w = 1.0 wt% and w = 2.0 wt%. The ironing limits of the cups were significantly increased by suspending SiO 2 in the lubricant VG170. In comparison to the results for VG10, the increase in viscosity of the lubricant enhanced the performance of the SiO 2 in the lubricant due to the formation of a thin film at the contact surface. The SiO 2 particles trapped in the thin film prevented the formation of local bonding among the asperities at the contact surface. The real ironing ratios of cup, r r and the photos of the die surfaces for different concentrations of SiO 2 suspended in the lubricant VG170 are shown in Fig. 9. The ironing limit for VG170 has increased from 25.4% for w = 0 wt% to a peak value of 34.7% with w = 1.0 wt%, taking into the consideration of the scatter present in the results. The maximum ironing ratio reduced to 33.9% when the concentration was excessive i.e., w = 2.0 wt%. Since the maximum ironing ratio dropped after w = 1.0 wt%, the experiment for w = 5.0 wt% was omitted. Cracks and seizures were observed for w = 1.0 wt% and Fig. 9. Real ironing ratios of cup and photos of die surface for different concentrations of SiO 2 suspended in lubricant VG170. w = 2.0 wt%, respectively when exceeding the ironing limit. The increase in viscosity resulted in the better performance of the particles under high contact pressure. Suspending a small amount of nanoparticles into a medium viscosity lubricant has significantly increased the seizure resistance of both the cup and ironing die surfaces, particularly when exceeding the ironing limit for w = 0 wt% Ironing limits for lubricant VG500 The photos of the ironed cups having a seizure or smooth surface for different concentrations of SiO 2 suspended in the lubricant VG500 are shown in Fig. 10. Although seizures were observed at r r = 34.8% and 34.3%, respectively, for w = 0.1 wt% and w = 0.5 wt%, Fig. 10. Photos of ironed A3003-O cylindrical cups for different concentrations of SiO 2 suspended in lubricant VG500.

7 810 C.J. Tan et al. / Journal of Materials Processing Technology 229 (2016) Fig. 11. Real ironing ratios of cup and photos of die surface for different concentrations of SiO 2 suspended in lubricant VG500. smooth cups having ironing ratios of 34.8% and 33.3% were successfully obtained for w = 1.0 wt% and w = 2.0 wt%, respectively. A lubricant having a high viscosity is essential for enhancing the performance of the SiO 2 at the contact surface. However, an excessive increase in viscosity slightly reduced the ironing limit of the cup due to the increase in the ironing load. The real ironing ratios of cup, r r and the photos of the die surfaces for different concentrations of SiO 2 suspended in the lubricant VG500 are shown in Fig. 11. In comparison to the results for VG10 and VG170, adding a small amount of nanoparticles i.e. w = 0.1 wt% into VG500 has significantly increased the maximum ironing ratio of the smooth cup from 24.6% to 28.7%. However, the degree of scatter was slightly higher than the former ones due to the uneven dispersion of the nanoparticles in the high viscosity oil. The ironing limit of 34.6% was obtained for VG500 with w = 2.0 wt%. The maximum ironing ratio was significantly reduced to 27.8% using excessive amount of nanoparticles i.e., w = 5.0 wt%. The ironing limit for VG500 was 0.1% less than the one for VG170 using double amount of nanoparticles. Hence, it is more economical to iron the cups with VG170 and w = 1.0 wt%. The addition of a small quantity of nanoparticles into a high viscosity lubricant has increased the seizure resistance of both the cup and ironing die surfaces. The SEM photos of cup surfaces taken at the same cup height i.e., 30 mm from the bottom for w = 0.0 wt% and w = 1.0 wt% are shown in Fig. 12. Some small white SiO 2 particles remained at the cup surface after the ironing process as shown in Fig. 12(b) Ironing loads for different concentrations of SiO 2 suspended in lubricants VG10, VG170 & VG500 The ironing loads for Al 3003-O cups having real ironing ratios around 25% for different lubricants and concentrations of SiO 2 are Fig. 12. SEM photos of cup surfaces taken at same height of 30 mm for w = 0.0 wt% and w = 1.0 wt%. Ironing load (kn) v =10 mm 2 /s, w=0 wt % v =10 mm 2 /s, w=5 wt % v =170 mm 2 /s, w=0 wt v =170 mm 2 /s, w=1 wt v =500 mm 2 /s, w=0 wt v =500 mm 2 /s, w=1 wt Stroke (mm) Fig. 13. Ironing loads for Al 3003-O cups having real ironing ratios around 25% for different lubricants and concentrations of SiO 2.

8 C.J. Tan et al. / Journal of Materials Processing Technology 229 (2016) Fig. 14. Surface profiles of ironed cups in axial direction having real ironing ratios around 25% for different lubricants and concentrations of SiO 2. Average surface roughness around circumference (µm) Before ironing R a = 0.35μm v =10 mm 2 /s, w=0 wt % v =10 mm 2 /s, w=5 wt % v =170 mm 2 /s, w=0 wt % v =170 mm 2 /s, w=1 wt % v =500 mm 2 /s, w=0 wt % v =500 mm 2 /s, w=1 wt % x Distance from bottom center, x (mm) Fig. 15. Average surface roughness around circumference of ironed cups having real ironing ratios around 25% for different lubricants and concentrations of SiO 2. shown in Fig. 13. The ironing loads increased when the viscosities of the lubricants were increased. Regardless of the type of lubricant used, the ironing loads for the cups formed with SiO 2 were higher than or equal to the ones formed with the lubricants only Surface profiles of ironed cups having real ironing ratios around 25% The surface profiles of ironed cups in the axial direction having real ironing ratios around 25% for different lubricants and concentrations of SiO 2 are shown in Fig. 14. For all types of lubricant, the average surface roughness of the ironed cups was not affected very much due to the nano-size and low concentration of the particles. The average surface roughness around the circumference of the ironed cups having real ironing ratios around 25% for different lubricants and concentrations of SiO 2 is shown in Fig. 15. Similar to the results shown in Fig. 14, the surface roughness around the circumference of the ironed cups was not affected very much due to the nano-size and low concentration of the particles Repetitive ironing of cups for VG10 and VG500 The comparison of the average ironing loads at real ironing ratios of around 25% between v = 10 mm 2 /s and v = 500 mm 2 /s for w = 0 wt% and w = 1 wt% in repetitive ironing of Al 3003-O cups is shown in Fig. 16. In this process, 20 samples of pre-drawn cups were repetitively pushed through the lapped die without re-polishing

9 812 C.J. Tan et al. / Journal of Materials Processing Technology 229 (2016) Fig. 16. Comparison of average ironing loads between v = 10 mm 2 /s and v = 500 mm 2 /s for w = 0 and 1 wt% in repetitive ironing of Al 3003-O cups. Average difference in height, Δ (mm) VG10 VG170 VG Concentration of SiO 2 (wt%) B3 A2 A3 B2 B4 A1 A4 B1 B Δ=A-B Fig. 17. Average difference in height between peak and valley of earring profiles at real ironing ratios of around 25% for different concentrations of SiO 2. the die at the end of each process. The surface condition of the die was observed at the end of each test. The test was stopped once seizures were observed at the die surface and the number of trials, n was recorded. For v = 10 mm 2 /s, a seizure was observed when n = 3. However, no seizure was observed for v = 500 mm 2 /s after 20 trials. Suspending SiO 2 in a lubricant with a low viscosity had no effect on increasing the seizure resistance of the die. Although the average ironing load increased with the viscosity of the lubricant, the load was not affected very much by the quantity of SiO Average difference in height between peak and valley of earring profiles for VG10, VG170 and VG500 A The average difference in height ( ) between the peak (A) and the valley (B) of the earring profiles at real ironing ratios of around 25% for different concentrations of SiO 2 are shown in Fig. 17. The average heights of A and B were obtained from 8 different locations i.e., 4 measurements for each value along the cup edges. Regardless the contents and the types of the lubricants, the values of cups ironed with lubricants containing nanoparticles were slightly smaller than the ones ironed with lubricants only. However, the differences are negligible as the cup profiles were formed during the pre-drawing process under the same conditions. The earring profiles of the drawn cups hardly changed during the ironing process. In fact, the earring profile of the cup is strongly dependent on the anisotropic property of the blank material. 5. Conclusions The effects of suspending SiO 2 nanoparticles in sulfur based mineral oil on increasing the ironing limit of Al 3003-O cylindrical cups are summarized below: i The ironing limit of the cup was significantly increased to 35.2% with a lubricant having a kinematic viscosity of 170 mm 2 /s containing 1.0 wt% of SiO 2. The limit was 10.4% higher than the one obtained with plain oil. ii For a low viscosity lubricant, the increase in ironing limit was very low only with a large quantity of SiO 2. iii The ironing limit was slightly reduced when the viscosity of the lubricant was too high. iv The surface roughness of the ironed cups was not affected by the presence of SiO 2. v The increase in ironing loads due to the presence of SiO 2 was not significant. vi The seizure resistance of both the cup and ironing die surfaces was significantly increased with the medium and high viscosity lubricants containing a small quantity of nanoparticles for obtaining high ironing ratios. Additional cost and effort are required for suspending the nanoparticles in the lubricants despite the successful formation of aluminium alloy cups at high ironing limits. Acknowledgements This study is supported by the AUN Seed-Net, JICA and the University of Malaya under Grant No. UM CRA1301&1401 and RP021A-13AET, respectively. The authors would like to thank Mr. Kai Sugiura for his assistance in the experiment. References Abe, Y., Fujita, T., Mori, K., Osakada, K., Effectiveness of cemented carbide and TiCN cermet dies in ironing. J. Jpn. Soc. Technol. Plast. 54 (634), (in Japanese).

10 C.J. Tan et al. / Journal of Materials Processing Technology 229 (2016) Hosoe, H., Hiratsuka, K., Minami, I., Hironaka, S., Lubricities of super fine SiO 2 particle as a solid lubricant. J. Ceram. Soc. Jpn. 105 (10), (in Japanese). Hosoe, H., Matsuda, K., Hironaka, S., Effect of cluster diamond on lubricity of lubricating grease. Zairyo Gijutsu 16 (1), (in Japanese). Ito, K., Adachi, K., Kato, K., Friction of Si 3N 4 ball /Si 3N 4 disk sliding in water with SiO2 nano-particles. Tribol. Online 1 2, Jiao, D., Zheng, S., Wang, Y., Guan, R., Cao, B., The tribology properties of alumina/silica composite nanoparticles as lubricant additives. Appl. Surface Sci. 257 (13), Katsuhiro, I., Masao, M., (1976). Process and apparatus for preparation of thin walled cylindrical vessels. US Patent No. US A. Kim, H., Sung, J.H., Sivakumar, R., Altan, T., Evaluation of stamping lubricants using the deep drawing test. Int. J. Mach. Tools Manuf. 47, Kim, H., Altan, T., Evaluation of stamping lubricants in forming advanced high strength steels (AHSS) using deep drawing and ironing tests. J. Mater. Process. Technol. 209, Kobayashi, K., Hironaka, S., Suzue, M., Ohta, Y., Lubricities of SiO 2 particles coated with carbon. J. Ceram. Soc. Jpn. 112 (4), (in Japanese). Kuno, O., Kuno, I., Iwao, K., Fukuyasu, Y., Mizutani, Y., Development of high efficiency press forming technology of large-sized lithium ion battery outer case for electric vehicle. Sokeizai 52 (12), (in Japanese). Moshksar, M.M., Kalvarzi, A.H., Ironing of aluminum cups. Mater. Manuf. Proceses 16 (4), Odell, I., A study of wall ironing by the finite element technique. J. Eng. Ind.-Trans. ASME 100, Sarhan, A.A.D., Sayuti, M., Hamdi, M., Reduction of power and lubricant oil consumption in milling process using a new SiO2 nanolubrication system. Int. J. Adv. Manuf. Technol. 63 (5 8), Sia, S.Y., Bassyony, E.Z., Sarhan, A.A.D., Development of SiO2 nanolubrication system to be used in sliding bearings. Int. J. Adv. Manuf. Technol. 71 (5), Tan, C.J., Chong, W.T., Hassan, M.A., End formation of a round tube into a square section having small corner radii. J. Mater. Process. Technol. 213 (9), Yamashita, M., Goto, M., Lubricant application know-how seen in the examples of materials difficult in forming. Drawing and lubrication of titanium sheet. Press Working 43 (10), (in Japanese). Yanagihara, K., Tani, Y., Murakami, Y., Proposal of new solid lubrication technology employing nm silica particles. Trans. Jpn. Soc. Mech. Eng. C 69 (688), (in Japanese).