Search or add a thesis

Advanced Search (Beta)
Home > Effect of Samarium Additions on Shape Memory and Thermomechanical Behavior of Iron Based Shape Memory Alloys

Effect of Samarium Additions on Shape Memory and Thermomechanical Behavior of Iron Based Shape Memory Alloys

Thesis Info

Access Option

External Link

Author

Shakoor, Rana Abdul

Program

PhD

Institute

Ghulam Ishaq Khan Institute of Engineering Sciences and Technology

City

Topi

Province

KPK

Country

Pakistan

Thesis Completing Year

2007

Thesis Completion Status

Completed

Subject

Applied Sciences

Language

English

Link

http://prr.hec.gov.pk/jspui/bitstream/123456789/2075/1/29S.pdf

Added

2021-02-17 19:49:13

Modified

2024-03-24 20:25:49

ARI ID

1676725994398

Similar


In the present work, a comparative study of the shape memory and thermomechanical behavior of four alloys containing different amount of samarium have been carried out at a strain rate of 0.08x10 -6 s -1 . After hot rolling, annealing and solution treatment, the alloy samples were tensile deformed at room temperature from 1% to 5% and were then recovered at 600̊C for 20 minutes repeatedly for six times to complete six training cycles. It has been found that the addition of samarium strengthens the austenitic matrix, increases the c/a ratio and reduces the grain size. It has been noticed that the addition of samarium (0.64 wt. %) improves the shape memory effect when the alloys were strained from 1% to 5%. This improvement in shape memory effect presumably can be regarded as the increase in strength, increase in c/a ratio and absence of ά (martensite). It has been further noticed that when samarium contents are gradually reduced from 0.64 % to 0.21% the shape memory effect decreases. The decrease in shape memory effect by the decrease in samarium contents can be attributed to decrease in strength, decrease in c/a ratio and formation of ά (martensite). It has been further noticed that the shape memory effect decreases with the increase in amount of strain. It is found that thermomechanical treatment (training) results in improvement of shape memory effect and has a significant influence on mechanical parameters like proof stress (σ 0.002 ), critical stress (σ 0.0008 ) and strain hardening exponent. The improvement in shape memory effect by thermomechanical treatment can be regarded as the effect of reduction in the values of proof stress and critical stress during training which facilitates the formation of ε (martensite). It has also been noticed that excessive training may result in the formation of ά (martensite) due to continuous softening of the alloy during training, thus degrading the shape memory effect. Finally, it has also been noticed that the addition of samarium increases the values of proof stress, critical stress and strain hardening exponent. Although the addition of samarium increases the values of proof stress, critical stress and strain hardening exponent yet it has not an adverse effect on shape memory effect.
Loading...
Loading...

Similar Books

Loading...

Similar Chapters

Loading...

Similar News

Loading...

Similar Articles

Loading...

Similar Article Headings

Loading...

یہ بھی وقت تھا

یہ بھی وقت تھا

یہ بھی ایک وقت تھا ہماری مائیں ہماری بہنیں عید سے پہلے ہماری رہائی کے لیے مظاہر ے کیا کرتی تھیں ہماری مائیں بھی کسی میکسم گورکی کی ماں سے کم نہیں تھیں ۔

آج حالات اس سے بدتر ہیں اب تو سیاسی قیدیوں کو غائب ہی کر دیا جا تا ہے مصطفی کانجو کو غائب کیے ہوئے پانچ مہینے ہو گئے ابھی تک کچھ پتہ نہیں کہ زندہ بھی ہے کہ نہیں۔ تصویر میں میری ماں شیخ عبدالقیوم کی بھتیجیاں اور دبنگ جیالی خالی سکینہ بادشاہ مرحومہ نمایاں ہیں جن کی بیٹی کی وڈیونیب ہیڈکواٹر کے باہر پولیس سے دست بدست لڑتے ہوئے وائرل ہوئی تھی ۔1986ء کمیٹی چوک راولپنڈی

 

نوجوانوں میں تعلیم و تربیت کے فقدان کا تدارک اور سدباب: سیرت مبارکہ کی روشنی میں

Youth is no doubt the asset of Muslim world. If they are utilized in charitable activities; in the protection of respect and honor; and developmental works, they can prove to be beneficial and a blessing. While if they are taken by destructive elements in their hands they will become source of destruction and harm. By providing proper Islamic education, our future will be in safe hands and will breath in an air of respect among other nations. In young age, deterioration in manners and moral corruption are alarming and cause mischief in society. Therefore, the interest taken in the problems of youth will result in a progressive society and ummah. Islam has given a special place to youth and has declared them future architect and leaders of humanity. The holy prophet S.A.W has given much importance to the youth and focused on them during his life time.  In Islamic history, Muslim youth has represented the Muslim world in golden words and has spread the message of Islam’s moral height and greatness to the coming generations and nations. Due to the importance of youth problem of the youth in current time regarding lack of education and training are particularly discussed in this article. The research article begins with the detailed study of the research done in the area of education and socialization of youth. Moreover, the importance of education and socialization has been discussed in the light of the teachings of Quran and Hadith. After this, decadence in education, factors responsible for the decadence in education and its worse consequences have been thoroughly discussed in the light of the teachings of Islam.  As there are several reasons responsible for the downfall of education like: parents, teachers, education system, society, state, preachers, political parties and media, therefore, responsibility of the remedy of this lack of proper education and socialization also depend on all these stake holders. In the end of the paper, recommendations are given for the cure of decadence in education.

Revocation and Revitalization of Democracy in Pakistan 1970 to 2010 an Analytical Study

Democracy is a modern system of conducting the State affairs. There are many more systems of administrating State dealings but the democracy is the idealistic and beneficial for human race. Samuel P. Huntington has divided modern democratic era in three phases. Pakistan is going through third wave of modern democratic phase. Pakistan has inherited democracy from the former colonial rulers of the undivided subcontinent. This study has depicted the promotion of democracy in Pakistan, usually since independence and prominently from 1970 to 2010. Pakistani democracy and its formation demands to take such measures, which are favourable for stabilizing democracy. Thus, the numerous voices of people will give birth to democracy. An important aspect of the study is the broad use of electronic media and internet information, major part of it is the interviews from politicians, technocrats, experts, sociologist, lawyers and economist, just to ensure the reliability of the study. The primary and secondary sources are also used in this study. The primary sources for this study are official documents, statements, regional and international surveys, reports, interviews and official record issued by the government and other archival sources. The secondary sources are books, journals, and newspapers to express the works of democracy in globalized world and Pakistan respectively. The all panorama of thesis is as under: The first chapter comprises introduction of democratic period from pre-partition times in this part of the world in the fifth decade of eighteen century in Calcutta. However, there were a few democratic institutions present in British ruled India. In 1885, they nurtured Indian National Congress (INC). Later on, to represent Muslim community in the subcontinent All India Muslim League (AIML) was formed in 1906. After the creation of Pakistan in 1947, the democratic process in Pakistan was in its inception, the leaders like Quaid-i-Azam Mohammad Ali Jinnah as Governor General and Nawabzada Liaqat Ali Khan as Prime Minister of Pakistan, were leading the caravan of democracy in Pakistan but after them democracy was derailed because of much political upheaval. Ultimately, Pakistan came in the grip of Martial Laws since 1958. The Chapter two deals with Zulfiqar Ali Bhutto era. In between Martial Laws, there was a short period of democratic rule of Prime Minister Zulfiqar Ali Bhutto, who brought the nation on the path of democracy by framing unanimously accepted constitution of 1973 of Islamic Republic of Pakistan. Eventually, the undemocratic forces of Pakistan ended his democratic rule. Zulfiqar Ali Bhutto was an industrious leader, his sophisticated decisions and nationalization policy under new democratic regime exhibited new phenomenal dimensions, which was appropriated for the democratization. The Chapter third elaborates democracy during General Zia-ul- Haq period in which Zia abrogated the constitution of 1973 to have perpetual grip over rule in Pakistan. General Zia held Presidential Referendum in 1984, non-party elections 1985, which proved to be useless for the democratization. Chapter four consists of unstable democratic first and second regimes of Mohtrama Benazir Bhutto and Nawaz Sharif. Both did not fulfil their democratic obligations, rather they promoted confrontational politics in the Pakistan. The Chapter fifth argues about the democracy during General Pervaiz Musharraf regime in which he held Referendum and Elections 2002, as a result King Party (PML-Q) got Sway and ruled over country in form of so-called inflexible or coalition democratic government. PML- N and PPP signed ‗Charter of Democracy‘ with all pomp and show. On the other hand, in 2007, democracy was derailed in Pakistan due to political predicaments in form of proclamation of state of emergency and abolition of judiciary. The Chapter six deals with Pakistan People‘s Party government (PPP) beginning from 2008, it restored the judiciary, amended 18th and 19th amendment successively. At the bottom of this thesis, conclusion has given in which all considerations of democratization in Pakistan have been analyzed.