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Power Consumption and Tool Wear Assessment when Machining Titanium Alloys
Salman Pervaiz,Ibrahim Deiab,Basil Darras 한국정밀공학회 2013 International Journal of Precision Engineering and Vol.14 No.6
Titanium alloys are of interest for aerospace industries due to their high strength to weight ratio, outstanding corrosion and erosion properties and ability to operate at higher temperature. They are classified as difficult to cut materials because of their low thermal conductivity, high chemical reactivity and high strength at elevated temperature. The machinability rating of titanium alloys is low compared to other materials from many aspects. This study focuses on studying the cutting tool wear and power consumption when machining Titanium alloys under different cutting conditions. Design of experiments was used to develop a test matrix that cover the range of cutting conditions recommended for machining titanium alloys. Cutting forces, power consumption, tool wear and surface roughness were measured and analyzed. Tool wear mechanisms were also studied using scanning electron microscopy.
Salman Pervaiz,Saqib Anwar,Imran Qureshi,Naveed Ahmed 한국정밀공학회 2019 International Journal of Precision Engineering and Vol.6 No.1
Titanium alloys are generally known as difficult-to-machine materials because of their low machinability ratings. Their usage is favored for demanding sectors because of their high strength to weight ratio, high corrosion resistance and ability to operate at elevated temperatures. Machining of titanium alloys results in higher environmental burden, because they require high energy and generous amount of cutting fluids during machining. It is a well-known fact that most of the cutting fluids are toxic and non-biodegradable in nature and their disposal is costly. Therefore, researchers in metal cutting are keen to explore the potential of minimum quantity lubrication (MQL) and minimum quantity cooling lubrication (MQCL) based cooling techniques as an alternate to conventional flood cooling. When MQL and MQCL techniques are used by employing biodegradable vegetable based oils then there is an encouraging potential of replacing the non-biodegradable cutting fluids. This study documents the recent experimental and numerical advances achieved in the MQL and MQCL assisted techniques for machining titanium alloys. The study also highlights the current challenges in this area and recommends future work to address these challenges.
Khalid Pervaiz Akhtar,Manzoor Hussain,Mahmood-Ul-Hassan,Muhammad Sarwar,Nighat Sarwar 한국식물병리학회 2015 Plant Pathology Journal Vol.31 No.2
Bt-cotton germplasm, consisting of 75 genotypes was evaluated against cotton leaf curl disease (CLCuD) under high inoculum pressure in the field and using graft inoculation in glasshouse by visual symptom scoring assessments. None of the tested genotype was found disease free under both evaluation tests. Under field conditions in 2011, 3 genotypes were found resistant, 4 moderately resistant, 3 tolerant, 2 moderately susceptible and one susceptible; in 2012, 3 genotypes were tolerant, 7 moderately susceptible, 5 susceptible and 38 highly susceptible; in 2013, one was moderately susceptible and 51 were highly susceptible with varying degree of percent disease index (PDI) and severity index (SI). However, through graft evaluation in glasshouse, none of the graft inoculated plant was symptomless. All tested genotypes showed disease symptoms with SI values ranging between 5.0 and 6.0, and latent period between 12 and 14 days. Of the 75 genotypes evaluated using graft inoculation, 11 were found susceptible with SI values of 5.0 to 5.4 while remaining 64 were highly susceptible with SI values of 5.5 to 6.0. Inoculated plants of all tested genotypes exhibited severe disease symptoms within 10 days after the appearance of initial symptoms. No reduction in SI value was observed until the end of the experiment i.e., 90 days after grafting. Information generated under the present study clearly demonstrates that no sources of resistance to CLCuD are available among the tested Bt-cotton genotypes. So, a breeding programme is needed to introgress the CLCuD-resistance from other resistant sources to agronomically suitable Bt-cotton genotypes.
Akhtar, Khalid Pervaiz,Hussain, Manzoor,Hassan, Mahmood-Ul,Sarwar, Muhammad,Sarwar, Nighat The Korean Society of Plant Pathology 2015 Plant Pathology Journal Vol.31 No.2
Bt-cotton germplasm, consisting of 75 genotypes was evaluated against cotton leaf curl disease (CLCuD) under high inoculum pressure in the field and using graft inoculation in glasshouse by visual symptom scoring assessments. None of the tested genotype was found disease free under both evaluation tests. Under field conditions in 2011, 3 genotypes were found resistant, 4 moderately resistant, 3 tolerant, 2 moderately susceptible and one susceptible; in 2012, 3 genotypes were tolerant, 7 moderately susceptible, 5 susceptible and 38 highly susceptible; in 2013, one was moderately susceptible and 51 were highly susceptible with varying degree of percent disease index (PDI) and severity index (SI). However, through graft evaluation in glasshouse, none of the graft inoculated plant was symptomless. All tested genotypes showed disease symptoms with SI values ranging between 5.0 and 6.0, and latent period between 12 and 14 days. Of the 75 genotypes evaluated using graft inoculation, 11 were found susceptible with SI values of 5.0 to 5.4 while remaining 64 were highly susceptible with SI values of 5.5 to 6.0. Inoculated plants of all tested genotypes exhibited severe disease symptoms within 10 days after the appearance of initial symptoms. No reduction in SI value was observed until the end of the experiment i.e., 90 days after grafting. Information generated under the present study clearly demonstrates that no sources of resistance to CLCuD are available among the tested Bt-cotton genotypes. So, a breeding programme is needed to introgress the CLCuD-resistance from other resistant sources to agronomically suitable Bt-cotton genotypes.
Akhtar, Khalid Pervaiz,Ahsanul Haq, M. The Korean Society of Plant Pathology 2003 Plant Pathology Journal Vol.19 No.5
This report described a simple, inexpensive, faster, and effective graft inoculation method for the artificial transmission of Mungbean yellow mosaic virus (MYMV). Success of grafting and disease transmission was 100% in this method. Screening of mungbean germplasm using this method will prevent the chance of escape infection, probably as a consequence of non-preference mechanism and loss of vector infectivity. The grafting method described here is applicable to both screenhouse and field trials.
An Improved Group Sampling Plan Based on Time-Truncated Life Tests
Aslam, Muhammad,Pervaiz, Muhammad Khalid,Jun, Chi-Hyuck The Korean Statistical Society 2010 Communications for statistical applications and me Vol.17 No.3
In this paper, a new group sampling plan for the lot acceptance is proposed for the time truncated life test, which can be utilized when multi-item testers are implemented. The design parameters are found using the two-point approach such that the producer's and consumer's risks are satisfied simultaneously at the acceptable reliability level and the lot tolerance reliability level, respectively. The case of Weibull distribution is described to illustrate the procedure that can be used when the quality level is expressed by a multiple of the specified life. The advantage of the proposed plan is demonstrated by comparing with the existing plan in terms of the sample size required. The tables are constructed and some examples are given to illustrate the procedure developed here.
Simran Kaur,Pervaiz Ahmed,Chong Yit Sean,Yunus Ali 글로벌지식마케팅경영학회 2020 Global Marketing Conference Vol.2020 No.11
A central focus area of this study is to investigate the distinctive way religion influences consumer behaviour in their consumption of brands by exploring the dynamics that take place when a brand transgression violates a religious norm. Specifically, the Halal consumption context was used in this study, where the brand transgression involved a breach by Halal-certified brands. This study applies the disconfirmation paradigm and posits that a brand transgression involving a violation of a religious norm, results in a unique disconfirmation of expectations that is beyond a consumer-brand relationship. Essentially, the present research explores trust levels and behavioural intentions after a brand transgression and the effectiveness of recovery strategies in mitigating the negative effects of a transgression. A scenario-based experimental approach was used to operationalise this research.
Atif Naveed Khan,Pervaiz Akhter,Gussan Maaz Mufti 보안공학연구지원센터 2016 International Journal of Smart Home Vol.10 No.5
Pakistan is an energy deficient country and the current power crisis of Pakistan is hampering its economic development. Pakistan is naturally benefitted with different renewable energy resources; out of which solar and wind energy are the main highlights. This research work will provide an assessment of the renewable energy potential of the Baluchistan region. A comparison of the economic and financial analysis for a centralized hybrid renewable energy system has been simulated by using Homer software. Three cases have been proposed in which centralized standalone solar PV system, centralized standalone wind energy system and a hybrid combination of both centralized standalone solar and wind energy system have been studied. Homer software has been used to devise the most optimal solution. The simulations confirm that the best optimal solution is the hybrid renewable energy system for the rural electrification of the proposed region.