Effect of Machining Parameters on Surface Quality of Aluminium Puncher for Microchannel Fabrication Using Micro Cutting Process

Precision and surface finish plays an important role in modern industry. Both of these elements are more challenging to achieve in micro-sized machining due to their extremely small size and ease of damage. The quality of surface roughness and accuracy is directly influenced by the machining parameters used. The present work involves a detailed experimental analysis of surface quality for microchannel fabrication. This experiment was formed using the Response Surface Methodology (RSM) method by using three main machining parameters namely spindle speed (r/min), feed rate (mm/min), and depth of cut (µm) to produce an Aluminium microchannel puncher. The results of the study show that the best surface roughness is obtained by the combination of the following parameters; spindle 14,000 r/min, feed rate of 90 mm/min, and depth of cut 50 µm. This study concludes that the surface roughness of Al6061 steel is greatly influenced by two main parameters, namely depth of cut and feed rate

Heuristic design of U-shaped die cooling channel for producing ultra-high strength steel using hot press forming

This paper proposes an optimised cooling channel design for a U-shaped die in the hot sheet metal forming process using a heuristic method. Unlike in previous works, the parameters used in this study for optimising the cooling channel design not only consider the pitch between and diameter of cooling channels but also their distance from the tool surface and wall tool. The cooling channel design is optimised by coupling the heuristic method with finite element thermal and static analyses. The main factors to be considered in the optimisation include the highest heat transfer and the lowest stress that can be achieved by the optimum cooling channel die design. The optimum design was determined by conducting a simulation and was validated by conducting an experiment. The temperature distribution of the FEA model was at most 5% different from the experimental results. The optimum cooling channel design of hot press sheet metal forming can produce ultra-high strength steels which tensile strength and hardness are 51 and 83% greater than those of original boron steels. The heuristic method can also be applied to optimise the cooling channel die design for the production of ultra-high strength steels in the automotive manufacturing industry

Experimental and Simulation Approach; Investigation Effect of Axial Feed Rate to the Cutting Force in Dimple Milling Using Ball End Mill Tool

A recent study indicated that the dimple has potential to improve the parts performance in a way of minimizing friction on a sliding mechanical component. Despite outnumbered dimple fabrication methods, milling process is considered as the versatile process that could produce various dimple profile with complex shape and the process is extremely dependent on the process variable such as machining parameters and cutting tool condition. The present research work aiming to study the effect of the milling machining parameters which is the axial feed rate and tool diameter to the cutting force by means of experimental work and finite element analysis (FEA). The concave dimple profile is machined at different axial feed rate to a flat Al6061 specimen using ball end mill attached to 3-axis CNC milling machine and the cutting force captured by KISTLER force dynamometer and the results will be compared with the FEA results. Based on the results, shows that cutting force increased directly proportional with the increasing plunging feed rates and tool diameters. The investigation work has successfully characterized the influence of studied milling parameters to the cutting forces and the research work will be continued further on the incline milling technique and micro size ball end mill

Effect of benzoyl treatment on the performance of sugar palm/kenaf fiber-reinforced polypropylene hybrid composites

The main purpose of this work is to investigate the effect of benzoyl treatment on the performance of sugar palm/kenaf fiber-reinforced polypropylene hybrid composites. Water absorption tests were carried out to confirm the effect of benzoylation treatment toward fabricating a more hydrophobic behavior of the hybrid composites. Both treated and untreated composites that have 10 wt.% of fiber loading with three different fiber ratios between sugar palm and kenaf (7:3, 5:5, 3:7) were analyzed. Physical and mechanical properties such as tensile, flexural, and impact strength were determined from this study. Morphological properties were obtained using scanning electron microscopy (SEM). It was found that the tensile strength of sugar palm/kenaf-reinforced polypropylene hybrid composites was improved with the treatment of benzoyl with a value of 19.41 MPa. In addition, hybrid composite with treated sugar palm and kenaf fiber T-SP3K7 recorded the highest impact and flexural strength of 19.4 MPa and 18.4 MPa, respectively. In addition, SEM demonstrated that surface treatment enhanced the mechanical properties of the hybrid composites. Overall, it can be suggested that benzoyl-treated composites with a higher volume of kenaf fiber than sugar palm fiber will improve the mechanical characteristics of the hybrid composites

Influence of cutting parameters to surface area roughness in dimple machining using milling process

Surface quality is among the predominant criterion in measuring machining process performance, including milling. It is extremely dependent on the process variable, such as cutting parameters and cutting tool conditions. The main intention of this research work is to study the effect of the milling machining parameters, including depth of cut, spindle speed, feed rate as well as machining pattern to the final surface area roughness of the fabricated dimple structure. The concave profile of the dimple is machined at the right angle to a flat Al6061 specimen using a ball end mill attached to a 3-axis CNC milling machine, and the surface area of the concave profile is measured using 3D measuring laser microscope. It is observed that surface area roughness reacts with the spindle speed and feed rate with different tool sizes. Based on the result gained, the work has successfully characterised the influence of studied milling parameters on the dimple surface area roughness, where within the range of the studied parameter, the surface area roughness varies only less than 2.2 μm. The research work will be continued further on the incline milling technique and micro size ball end mill

Isolation and molecular identification of Nipah virus from pigs

Nipah viruses from pigs from a Malaysian 1998 out-break were isolated and sequenced. At least two different Nipah virus strains, including a previously unreported strain, were identified. The findings highlight the possibility that the Malaysia outbreaks had two origins of Nipah virus infections

Detection of Koi herpesvirus (KHV) in Cyprinius carpio (Koi) stocks using enzyme-linked immunosorbent assay (ELISA)

Koi herpesvirus (KHV), which is also known as Cyprinid herpesvirus 3 (CyHV-3) infection, is an OIE(international des epizootis) listed disease that caused high losses in common and koi carp in Indonesiaand Japan in 2002 and 2003. Since the mid of 2006, the polymerase chain reaction (PCR) has been usedin Malaysia for surveillance of koi fingerlings to detect virus nucleic acid, but it has been found to produceunreliable results. Following this, an alternative enzyme-link immunosorbent assay (ELISA) technique forthe detection of antibody against KHV was used to find evidence of KHV infection in koi carp stocks on farmsthat had been sampled for the PCR. For this purpose, a total of 245 serum samples from koi carp stocks werecollected and tested for the antibody to KHV by the ELISA at the Centre for Environment, Fisheries andAquaculture Science (CEFAS) laboratory, Weymouth, UK. Two hundred and eight samples were found to benegative but 37 others were either definitely positive or close to borderline positive and all were retested. Thefinal results showed that 222 (90%) samples were confirmed as negative and 19 (8%) others were definitelypositive. Meanwhile, four samples (1.6%) were positive at dilutions of 1:400 or 1:200, but cross reactionswith CyHV-1 (causing herpesviral epidermal hyperplasia) could have occurred at those dilutions. Three of thesamples were the only positive fish at two sites, but the fourth sample came from a site at which there were 4definite positive samples (from 20 fish sampled). Thus this study confirmed that Malaysian koi stocks havepreviously been exposed to KHV. With the lack of bio-security measures and awareness, there was a highprobability that the koi carp had been exposed to KHV, leading to subclinical infections and some fish mightpossibly have become carriers of the virus. Hence, further surveillance needs to be conducted to determinethe true situation of the KHV infection in Malaysia

An overview of moisture damage performance tests on asphalt mixtures

This paper presents a review of moisture damage performance tests on asphalt mixtures. The moisture damage remains to be a detriment to the durability of the Hot Mix Asphalt (HMA) pavement. Moisture damage can be defined in forms of adhesive failure between bitumen and aggregates and cohesive failure within bitumen. Aggregate mineralogy, bitumen characteristics and anti-stripping additive dominantly influence the performance of asphalt mixtures towards moisture damage alongside construction methods, climate and traffic loading. Various laboratory test methods have been developed to quantify the moisture damage performance of asphalt mixtures by resembles the action in the field, including qualitative test such as Boiling Water Test (ASTM D3625) and quantitative tests such as Modified Lottman Test (AASHTO T283). Both of these tests consist of two phases, which are conditioning and evaluation phase. This paper will review the effectiveness of the selected available tests based on various asphalt mixtures materials. Generally, this study indicates that asphalt mixtures consisted of limestone aggregates, modified bitumen and addition of anti-stripping additives will provide more resistant towards moisture damage

Evaluating potential of diatomite as anti clogging agent for porous asphalt mixture

Clogging is a major problem that occurs throughout the service life of porous asphalt due to the open nature of the mixture itself. Diatomite with characteristic of abrasiveness and porous structure seems to have potential in order to remove the clogging materials that mainly consists of soils. This study aims to investigate the effects of diatomite as anti-clogging agent on the permeability rate and strength of porous asphalt. The porous asphalt samples were prepared using Malaysia aggregate gradation and polymer modified bitumen of PG76 was used as the binder. This study focuses on clay as the clogging material at different concentration. A fixed amount of 0.5 g/L diatomite was applied to the porous asphalt samples as an anti-clogging agent prior to clogging cycles. The permeability test and resilient modulus were then conducted at different clogging concentrations (0.5, 1.0, 1.5 g/L) and cycles, with and without diatomite. It was found that samples with diatomite have a higher permeability rate compared to those without any application of diatomite after a few clogging cycles. As the clogging cycles increase, the clogging materials have trapped and filled up the voids in the porous asphalt samples and increase the resilient modulus result