Utilization of failure analysis tools necessitates a deep knowledge and capability of interpretation of results. Dr. Ensha’s years of experience in SEM fractography of metals, plastics and ceramics are valuable assets in failure analysis investigations. Frequently, his graduate studies and background in micro-mechanisms of fracture and fracture mechanics are leveraged for in-depth examination of failed parts in cases requiring advanced interpretation. Utilizing these interpretations, it is possible to delineate the root cause of failures in complex cases. The application of failure analysis and investigation during manufacturing can result in failure prevention, design modification and alternate materials selection.
Failures, in general, are often due to a design issue, a manufacturing issue or service condition. Seeking the root cause frequently requires a dynamic investigation strategy informed by years of experience. Whether a part is manufactured by casting, forming, forging, machining or combination, Dr. Ensha can systematically arrive at valuable conclusions.
The failure mechanisms causing a part to fail are numerous. The failure mechanisms examined by Dr. Ensha include: brittle and catastrophic fractures, conventional fatigue failures from extremely low-cycle to gigacycle, dwell sensitive fatigue and creep-fatigue, embrittlement, stress corrosion cracking, corrosion in solutions and gaseous environments. Interpreting these failure modes ultimately allows prevention and improved designs.
Dr. Ensha’s practical industrial experience covers wide applications in aerospace. Of the fasteners, gears, ball bearings, and shafts that have failed, many have been from aircraft turbines, fuselages, landing gears, commercial aircraft anti-skid brake system, hydraulic systems including manifolds, hoses, filter housing, to devices such as LVDT and engine temperature sensors in jet engines.
In the area of ground transportation, Dr. Ensha’s experience ranges from engine parts such as exhaust valves in the diesel engines of earth movers, to axel and lug nut failure in automobiles.
In the area of electronic metallurgy, Dr. Ensha also has performed many failure investigations dealing with surface mount failures and die-attach problems among others.