the effect of micropits and bio-lubricants on aluminum cold work extrusion performances

Many attempts have been made to replace mineral oil-based with biodegradable lubricant such as vegetable oil in order to reduce environmental impacts. Palm oil based is available in abundance in Malaysia at cheaper price compared to mineral based lubricant but reports on using this oil as an alternative lubricant is hardly found especially in cold metal forming applications. This study aims to evaluate and compare the tribological performances between two different types of palm oil-based and mineral oil-based lubricants using modified die surface geometry (with and without micropits at top and bottom positions, sharp T45 and radius R45 taper angle) during cold extrusion process. All extrusion process parameters were fixed during experiments, i.e. deformation ratio (3:1), speed range (8.1-8.3 mm/s), piston displacement stroke (40 mm), micropit depth (30 µm), diameter (600 µm), distance (1 mm) and 27 percent of area density. Top position of micropit exhibits the lowest friction and extrusion load with finer billet surface in all trials. It is also found that palm stearin (PS) performs better than palm kernel (PK) in terms of extrusion load and billet surface roughness. Similar results also obtained in paraffinic mineral oils experiments where VG460 outperforms VG95. Higher viscosity in both type of lubricants is the main reason that contributes to this performance. Comparing between PS and VG460, the performance of mineral oilbased is still superior than palm oil-based but the difference is very marginal in terms of extrusion load and billet surface roughness. The achievable extrusion load and billet surface finish under PS lubricant are 48.9 kN and 0.11µm respectively. The optimum tribological performance of mineral oil-based VG460 over palm oil-based PS is attributed to the large viscosity difference between VG460 (1347.60 mm2/s) and the PS (48.29 mm2/s). Since there is only marginal difference in tribological performance, it can be concluded that palm oil-based has a great potential to be developed further as an environmental friendly lubricant for replacing mineral oilbased type

Elements of Digital Technology Needs Among Technical and Vocational Education Students

This study was conducted to identify digital technology needs among final year students of Technical and Vocational Education (TVE) at the School of Education, Universiti Teknologi Malaysia (UTM)-. The elements selected for this study are the students' technical skills, attitudes and the availability of facilities. A questionnaire was used as a research instrument in this quantitative study. A total of 89 respondents were selected at random. The collected data was analyzed using the Statistical Package Social Sciences (SPSS) software version 26.0 to obtain frequency values, percentages (%), means, and standard deviations. According to the findings of the study, the need for digital technology among final-year TVE students is satisfactory, with the mean value for the entire research question obtained being 3.50 at a moderate score level. Therefore, the School of Education at UTM needs to increase the need for the use of digital technology to facilitate students in the teaching and learning process

Impacts of conceive-design-implement-operate knowledge and skills for innovative capstone project

Nowadays, the competitions among countries to recruit engineering students as workers do not focus on talents, but also on the reserve of it. The advancement of education in engineering field plays a big part in enhancing comprehensive domestic strength because the scientific revolution will contribute to important modifications of the industrial landscape. Therefore, Conceive- Design-Implement-Operate (CDIO) understanding and techniques are required for enhancing this field of education particularly for innovation of capstone project. Thus, this study was identified student knowledge and skills consist of teamwork, problem-solving, and communication skills of the CDIO in capstone project involved two faculties which are Faculty of Biosciences & Medical Engineering (FBME) and Faculty of Electrical Engineering (FKE) at Universiti Teknologi Malaysia (UTM). Our respondents consist of 28 and 30 of third-year students from FBME and FKE respectively. Besides, this study also was identified the importance of the CDIO approach in the innovative capstone project. The method that used was a quantitative survey by using 5 Likert scale questionnaires. The average mean for all research questions indicated that the majority of respondents agreed that the CDIO knowledge and skills in the capstone project are important in engineering education. Hence, the engineering students must possess not only the skills such as teamwork, problem-solving, and communication but also needs more knowledge that helps them to employability and adapt to real-world engineering problems

Influence of micro-pits indentation and palm based-oil on taper die sliding contact surface in cold extrusion process

Surface texturing is among the cheapest solutions for die modification if compared to tool change and hot works. In extrusion die design, the addition of micro-pits has increasingly been used to balance the metal flow. Such balance is particularly important for multiple cavity dies or sections with varying thicknesses in order to maintain a uniform velocity profile across the face of the die. In this research, surface texturing (called as micro-pits) was embedded on taper die sliding contact surface to explore its effectiveness on finish product of cold extrusion process. Palm oil based lubricants were tested for cold extrusion processes and mineral oils were used for comparison purpose. It was found that taper die with micro-pits (PA) performed a lessened extrusion load than taper die without micro-pits (NA), so as enhanced the performance of other tests parameter. In addition, viscosity of lubricant seems to be very important in ensuring that no material and tribological failures occur during the metal forming process

Lubricant viscosity: evaluation between existing and alternative lubricant in metal forming process

Lubrication in metal forming process is very important to control wear and friction at the interface between interacting surfaces. Non-renewable resources, such as mineral oil are widely used since a beginning due to its ability to act as a reservoir to the wearing contact which functions as a film material or sustains chemical transformation to become a film material. There is big concern that an alternative metal forming lubricant with similar viscosity able to replace existing metal forming lubricant without neglecting all main factors as demanded by industries. Two additives free paraffinic mineral oil with variable viscosity; VG95 and VG460 and daphnee were choose as existing lubricants, and is compared to an alternative lubricant with similar viscosity; RBD palm stearin and RBD palm kernel. The experiment used a cold work extrusion apparatus consisting of a pair of taper die and a symmetrical work piece (billet). The billet material was annealed pure aluminum A1100 with 45 of edge at the deformation area. It was found that lubricant with high viscosity performed slightly low extrusion load, but resulting higher surface roughness than low viscosity lubricants. However they show no severe wear on product surface

Evaluation of paraffinic mineral oil as lubricant in cold work extrusion process

In this paper, the effect of frictional constraint from the application of three different viscosity of additive free paraffinic mineral oil as lubricant were investigated by cold work forward plane strain extrusion experiments. The experiment used a cold work plane strain extrusion apparatus consist of a pair of taper die and a symmetrical workpiece (billet). The billet material was annealed pure aluminum A1100 with radius 5 mm in deformation area. The experimental result shows that the higher viscosity, will lead to lower friction effect to the deformed area, as well as product area

Non-edible palm oil : alternative to mineral based lubricant in metal forming process

In this paper, the effect of non-edible oil in cold extrusion process were investigated by cold work forward plane strain extrusion experiments. It then was compared to existing metal forming lubricant additive free paraffinic mineral oil, VG95 and commercial extrusion oil. A pair of taper die and a symmetrical work piece (billet) was placed inside extrusion rig which acted as main experimental apparatus. The experimental result shows that nonedible oil has similar maximum extrusion load with mineral based lubricant and commercial extrusion oil