FATIGUE ON ENGINE PISTONS By: Trushal Vora – ME Theeban Muniandy – ME Chong Kah Luo – ME Section: 06 Lecturer: Miss Alicia a/p Philip

OUR ABSTRACT Engine pistons are one of the most complex components among all automotive or other industry field components. The engine can be called the heart of a car and the piston may be considered the most important part of an engine. There are lots of research works proposing, for engine pistons, new geometries, materials and manufacturing techniques, and this evolution has undergone with a continuous improvement over the last decades and required thorough examination of the smallest details. Notwithstanding all these studies, there are a huge number of damaged pistons. Damage mechanisms have different origins and are mainly wear, temperature, and fatigue related. Among the fatigue damages, thermal fatigue and mechanical fatigue, either at room or at high temperature, play a prominent role. This work is concerned only with the analysis of fatigue-damaged pistons. Pistons from petrol and diesel engines, from automobiles, motorcycles and trains will be analyzed. Damages initiated at the crown, ring grooves, pin holes and skirt are assessed. A compendium of case studies of fatigue-damaged pistons is presented. An analysis of both thermal fatigue and mechanical fatigue damages is presented and analyzed in this work. A linear static stress analysis, using ‘‘cosmos works’’, is used to determine the stress distribution during the combustion. Stresses at the piston crown and pin holes, as well as stresses at the grooves and skirt as a function of land clearances are also presented. A fractographic study is carried out in order to confirm crack initiation sites.

TYPE OF ABSTRACT Informative abstract -The majority of abstracts are informative. While they still do not critique or evaluate a work, they do more other than describing it. -A good informative abstract acts as a surrogate for the work itself. -The writer presents and explains all the main arguments and the important results and evidence in the complete article/paper/book. - An informative abstract includes the information that can be found in a descriptive abstract (purpose, methods, scope) but also includes the results and conclusions of the research and the recommendations of the author.

KEY PROCESS ELEMENTS OF THE ABSTRACT Reasons: - To show that engine fatigue is not a small issue. It can develop into big problems if left unattended. - A vehicle enthusiast will be interested to learn more on their vehicle. Therefore, they can actually refer this journal to know more on engine piston fatigue. Problems: - This work will attempt to solve the problem faced by any vehicle users. Damages initiated at the crown, ring grooves, pin holes and skirt are assessed.

Scope: - Investigating in the field of thermal and heat damage on engine piston Fatigue is not responsible for biggest slice of damaged pistons, it remains a problem on engine pistons and its solution remains a goal for piston manufacturers. And it will last a problem for long because efforts on fuel consumption reduction and power increase will push to the limit weight reduction, that means thinner walls and higher stresses. Methodology: - A compendium of case studies of fatigue-damaged pistons. - Cosmos Works is used to determine the stress distribution on the engine piston. - Fractographic study is carried out to confirm crack initiation sites.

Implication: - Engine piston stress can only be reduced and cannot be totally overcome. - To reduce engine piston stress, more studies should be carried out to investigate the relationship between types of engine piston and heat produced.

COMPONENTS OF ABSTRACT Components: 1.Reason for writing ✓ 2.Problem ✓ 3.Methodology ✓ 4.Results X 5.Implications ✓ All components are mentioned by the author except for Results.

LANGUAGE USED IN THIS ABSTRACT The language used in this journal is: 1.British English 2.Present tense 3.Precise 4.Powerful 5.Clear 6.Technical terms

CHARACTERISTIC OF ABSTRACT LENGTH/PARAGRAPH This abstract has a medium length. At the same time, the information are sufficient and reliable. This abstract contains 3 paragraphs. 1 st paragraph – description of engine piston fatigue. 2 nd paragraph – pistons in the automobile industry. 3 rd paragraph – type of studies carried out.

CREDITS/REFERENCE F.S. Silva, "Engineering Failure Analysis", Fatigue on engine pistons – A compendium of case studies, vol. 13, pp , July UNC College of Arts and Science, The Writing Center, [online] (Accessed 26 th December 2013) Slides: Trushal Vora Journal: Chong Kah Luo Information finding: Theeban Muniandy Examiner: Miss Alicia