Effect of Orientation of Reinforcements on the Quality of the Machined Surface in Machining Aluminium Composites

2013 ◽  
Vol 774-776 ◽  
pp. 1032-1037
Author(s):  
Da Zhen Wang ◽  
Pei Feng Feng

The precision turning experiments of aluminium composites reinforced with SiC whisker reinforcements were done by polycrystalloid diamond (PCD) tools. The measure analysis of the machined surface was carried out with Atom Force Microscope (AFM) and Scan Electronic Microscope (SEM). The roughness values of the machined surface were measured by Talysurf-6. The results show that the orientation of reinforcements in the machined surface will directly affect the deformation mechanism of SiC whiskers, microstructures of the machined surface, and to determine the quality of the machined surface. In the five types from A to E of SiC whisker orientation, the orientation of case A easily makes to produce SiC whisker deformation by cutting off directly, and to result in the best machined surface. However, for the orientation of case E, it easily makes to induce SiC whisker deformation by pulling out or pressing into aluminium matrix, and to produce the worst machined surface.

2012 ◽  
Vol 622-623 ◽  
pp. 399-403 ◽  
Author(s):  
Tarun Thomas George ◽  
J. Venugopal ◽  
M. Anthony Xavior ◽  
R. Vinayagamoorthy

The quality of a machined surface is becoming more and more important to satisfy the increasing demands of sophisticated component performance, longevity, and reliability. The objective of this paper is to analyze the performance of precision turning using conventional lathe on Ti6Al4V under dry working conditions. Various parameters that affect the machining processes were identified and a consensus was reached regarding its values. The proposed work is to perform machining under the selected levels of conditions and parameters and to estimate the, cutting temperature and surface roughness generated as the result of the machining process. ANOVA is used to find the percentage contribution of each parameter to the surface roughness and cutting temperature.


2014 ◽  
Vol 800-801 ◽  
pp. 576-579
Author(s):  
Lin Hua Hu ◽  
Ming Zhou ◽  
Yu Liang Zhang

In this work, cutting experiments were carried out on titanium alloy Ti6Al4V by using polycrystalline diamond (PCD) tools to investigate the effects of the tool geometries and cutting parameters on machined surface roughness. Experimental results show machined surface roughness decreases with increases in the flank angle, tool nose radius and cutting speed within a limited range respectively, and begins to increase as the factors reaches to certain values respectively. And machined surface roughness decreases with increases in feed rate and cutting depth respectively.


2011 ◽  
Vol 70 ◽  
pp. 315-320 ◽  
Author(s):  
Riaz Muhammad ◽  
Agostino Maurotto ◽  
Anish Roy ◽  
Vadim V. Silberschmidt

Analysis of the cutting process in machining of advanced alloys, which are typically difficult-to-machine materials, is a challenge that needs to be addressed. In a machining operation, cutting forces causes severe deformations in the proximity of the cutting edge, producing high stresses, strain, strain-rates and temperatures in the workpiece that ultimately affect the quality of the machined surface. In the present work, cutting forces generated in a vibro-impact and hot vibro-impact machining process of Ti-based alloy, using an in-house Ultrasonically Assisted Turning (UAT) setup, are studied. A three-dimensional, thermo-mechanically coupled, finite element model was developed to study the thermal and mechanical processes in the cutting zone for the various machining processes. Several advantages of ultrasonically assisted turning and hot ultrasonically assisted turning are demonstrated when compared to conventional turning.


In this study, pre-gelatinized simple corn flour with microwave and three levels of Balangu Shirazi gum were used in producing gluten free bread. The substructure of two types of flour was evaluated using the electronic microscope. The properties of bread samples including moisture, specific volume, porosity, crust color, texture and overall acceptance were studied. The results of electronic microscope showed that the granular structure of corn flour was coherent. However, the granular structure of pre-gelatinized corn flour had more structural expansion and swell because of demolished heat. In addition, samples containing pre-gelatinized corn flour and 2% Balangu Shirazi gum had the highest humidity in the first (22.5%) and third (19.4%) day. The highest porosity (23.3% and 23.5%) and specific volume (4.9 and 5.1 cm3 /g) and the minimal texture firmness were observed within 1 day after manufacturing (4.8 & 4.9 Newton) in samples containing pregelatinized corn flour and two levels of Balangu Shirazi gum (1% and 2%). Moreover, the results showed that increased L* colorful component (52% increase) caused by using the pre-gelatinized corn flour and raising the consumption level of gum. The presence of gum didn’t have a significant impact on two colorful components such as a* and b*. The use of pregelatinized corn flour resulted in decreasing b* colorful component. Also, sensory evaluations gave the highest score of overall acceptance to samples containing pre-gelatinized corn flour and two levels of Balangu Shirazi gum (1% and 2%).


2019 ◽  
Vol 88 (2) ◽  
pp. 187-192 ◽  
Author(s):  
Cecilia Vullo ◽  
Marina Meligrana ◽  
Adolfo Maria Tambella ◽  
Angela Palumbo Piccionello ◽  
Fabrizio Dini ◽  
...  

The aim of this experimental study was to evaluate the sedative and cardiorespiratory effects of alfaxalone and midazolam after intramuscular administration in pigs. Fourteen pigs, weighing 18 to 22 kg, aged between 55 and 70 days, American Society of Anaesthesiologists classification 2, affected by congenital reducible umbilical hernia, were included in the study. Alfaxalone (5 mg/kg) and midazolam (0.5 mg/kg) mixed in the same syringe were administered into the neck muscle. Pain on injection, quality of sedation and time to achieve lateral recumbency were recorded. Heart rate (HR), respiratory frequency (fR), and rectal temperature (RT) were recorded at 0 (baseline: before drug administration), 10, 15, and 20 min after the injection. Oxygen saturation of haemoglobin (SpO2), arterial blood pH, arterial oxygen (PaO2) and carbon dioxide (PaCO2) tensions and bicarbonate concentration (HCO3-) were recorded at 10, 15, and 20 min after injection. Continuous data were analysed using a repeated-measure analysis of variance (ANOVA) and a P-value < 0.05 was considered significant. Ten animals out of fourteen showed no pain on injection, whereas the remaining four exhibited mild pain. The time from the end of injection to lateral recumbency was 266 ± 40 s. The quality of sedation ranged between good to very good. No significant changes in the variables monitored were observed between the time points. In conclusion, the intramuscular administration of alfaxalone and midazolam in pigs at the doses used induced reliable and fast sedation, without pain on injection and moderate respiratory effects.


2019 ◽  
Vol 4 (2) ◽  
pp. 94-103
Author(s):  
Zulkani Sinaga ◽  
Achmad Muhazir ◽  
Muhamad Ilham Fuadi

ABSTRAKPenelitian ini dilakukan pada salah satu produsen spare part otomotif PT. XYZ memiliki permasalahan dan menjadi perhatian serius pada bagian pengelasan adanya produk cacat yang dapat menurunkan nilai dan kualitas produk sehingga banyak produk yang ditolak oleh konsumen karena tidak sesuai dengan standar, dimana banyak terdapat kotoran las (Spatter) yang menmpel pada Joint Exhaust produk Half Outer Comp merupakan bagian komponen dari knalpot sehingga mengurangi produktifitas produksi pada bagian inspeksi akhir, permasalahan di atas dianggap perlu dilakukan penelitian untuk mencari penyebab hal tersebut. Beberapa langkah dilakukan guna memperbaiki cacat yang ada yaitu langkah awal dilakukan observasi dan wawancara ke bagian produksi, metode yang digunakan untuk pengolahan data hasil observasi menggunakan metode DMAIC (Define, Measure, Analisys, Improve, Control), kemudian dilakukan optimalisasi dan modifikasi Jig Welding dengan mendesain ulang menggunakan perangkat software Solidwork versi 2018, kemudian mengubah posisi Jig sebelumnya vertikal menjadi horizontal agar supaya pada saat pengelasan Spatter tidak langsung jatuh ke Joint Exhaust dan memberikan penahan tambahan pada Jig guna mengurangi jumlah Spatter menempel pada Half Outer Comp. Pada penelitian ini diperoleh hasil dimana jumlah Spatter yang menempel pada Joint Exhaust sangat berkurang dan memperoleh hasil produk yang lebih baik sehingga meningkatkan produktivitas pada bagian inspeksi akhir sebelumnya 58,33% menjadi sebesar 83.33%.  Kata Kunci :  Optimalisasi, Spatter, DMAIC, Desain, Solidwork 2018 ABSTRACTThis research was conducted at one of the automotive spare part manufacturers PT. XYZ has a problem and is a serious concern on the welding part of the presence of defective products that can reduce the value and quality of the product so that many products are rejected by consumers because it does not comply with standards, where there is a lot of welding dirt (Spatter) which attaches to the Joint Exhaust Half Outer Comp product is a component of the muffler so as to reduce production productivity at the final inspection, the above problems are considered necessary to do research to find the cause of it. Several steps were taken to correct existing defects, namely the initial steps carried out observation and interviews to the production department, the method used for processing the observation data using the DMAIC method (Define, Measure, Analysis, Improve, Control), then optimization and modification of Jig Welding with redesign using the 2018 Solidwork software tool, then changing the position of the previous vertical jig to horizontal so that when welding Spatter does not directly fall into the Joint Exhaust and provide additional support to the Jig to reduce the number of Spatter attached to the Half Outer Comp. In this study the results obtained where the number of Spatter attached to the Joint Exhaust is greatly reduced and obtain better product results thereby increasing productivity in the previous final inspection section of 58.33% to 83.33%. Keywords : Optimization, Spatter, DMAIC, Design, Solidwork 2018


2015 ◽  
Vol 3 (2) ◽  
Author(s):  
Syed Adnan Ahmed ◽  
Jeong Hoon Ko ◽  
Sathyan Subbiah ◽  
Swee Hock Yeo

This paper describes a new method of microtexture generation in precision machining through self-excited vibrations of a diamond cutting tool. Conventionally, a cutting tool vibration or chatter is detrimental to the quality of the machined surface. In this study, an attempt is made to use the cutting tool's self-excited vibration during a cutting beneficially to generate microtextures. This approach is named as “controlled chatter machining (CCM).” Modal analysis is first performed to study the dynamic behavior of the cutting tool. Turning processes are then conducted by varying the tool holder length as a means to control vibration. The experimental results indicate that the self-excited diamond cutting tool can generate microtextures of various shapes, which depend on the cutting tool shank, cutting speed, feed, and cutting depth. The potential application of this proposed technique is to create microtextures in microchannels and microcavities to be used in mass and heat transfer applications.


2021 ◽  
pp. 200-206
Author(s):  
I.N. Sedinin ◽  
V.F. Makarov

It is considered the complex of operations of the technological process for the heat treatment of steel 95X18-Sh, as a result of which the material of the samples increases the hardness to 59...61 HRC, and also improves the physical and mechanical properties. A full-scale full factorial experiment of face milling of samples was carried out using the method of mathematical planning. In the experiments, a high-precision machine and a carbide cutting tool were used. To calculate the values of the roughness function, the following are taken as independent variables: cutting speed, feed per tooth and depth of cut. In order to determine the coefficients of the linear equation, a central compositional orthogonal plan of the second order for three factors was used. A matrix of levels of variation of independent variable factors and a matrix of experiment planning were compiled. A regression analysis of the obtained experimental statistical data was carried out using the Microsoft Excel, Statistica and Wolfram Alpha programs. As a result of the calculations, a mathematical model of the roughness of the machined surface and optimal cutting conditions were determined.


2019 ◽  
Vol 19 (01) ◽  
pp. 2050006 ◽  
Author(s):  
Muhammad Owais Qadri ◽  
Hamidreza Namazi

Analysis of surface quality of machined workpiece is an important issue in machining of materials. For this purpose, scientists analyze how the texture of machined surface changes due to different conditions. Machine vibration is one of the factors that highly affects the surface quality of machined surface. In this research, we analyze the relation between machine vibration and surface quality of machined workpiece. For this purpose, we employ fractal theory and analyze how the complex structure of machined surface changes with the complex structure of machine vibration signal in case of variations of machining parameters, namely, depth of cut, feed rate and spindle speed, in milling operation. Based on the results, variations of surface quality of machined workpiece are related with the variations of complexity of machine vibration signal. The method of analysis employed in this research can be applied to other machining operations in order to find the relation between machine vibration and surface quality of machined workpiece.


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