Books.google.co.th - This volume comprises papers presented at the 2nd International Conference on Advanced Nondestructive Evaluation (ANDE 2007) held in Busan, Korea, on October 17-19, 2007. Many of the excellent papers included in this book show the current state of nondestructive technologies, which are experiencing rapid.
![]() Advanced Nondestructive Evaluation II - Proceedings of the International Conference on Ande 2007. Failure Analysis of Cracked Impeller Blades SUMMARY: Two blade samples of a cracked ******************* centrifugal blower impeller blade was submitted for metallurgical analysis of the cracks. The cracks in the submitted blade samples were found to have initiated at corrosion pits on the leading edge of the blades. Download Reikan FoCal Pro Ver 2.0 Full (crack included) Download Reikan FoCal Pro Ver 2.0 Full (crack included) FoCal Pro from Reikan is purpose designed to provide a comprehensive and accurate way to focus calibrate and test most modern Canon and Nikon DSLR cameras and lenses. Included with each FoCal Pro purchase is the licence key to use. Initial propagation was by stress corrosion cracking (SCC). Further propagation occurred by corrosion assisted fatigue throughout the remaining crack lengths. The maximum depth of SCC was found to be about 0.370 inch from the leading edge surface. The initiation site of the main crack was found to be slightly beyond the toe of an assembly weld. Minor secondary cracks were found in the same region. Both blade samples submitted exhibited corrosion pitting mainly concentrated along their leading edges. None to very little of a protective coating remained at the location of cracking. Energy dispersive x-ray spectrographic (EDS) analysis taken along the attack front of a longitudinal metallurgical cross-section taken through a corrosion pit indicated significant amounts of lead, sulfur and a trace of chlorine. Chlorides and sulfides are known to cause SCC in high strength PH stainless steels. High temperature water may also cause SCC in 17-4 PH stainless steel. Lead can cause cracking by solid (or liquid) metal-induced embrittlement, although none was observed in the submitted pieces. The blade base metal and remnant weld metal were determined to be 17-4 PH by optical emission spectroscopy. The microstructure of the blades was tempered martensite, typical of 17-4 PH in the hardened condition. The microstructure exhibited some carbide precipitation at the grain boundaries; however, SCC cracking was found to be mainly transgranular. Cracking was limited to the area where the coating had been removed during service. The coating appeared to protect the rest of the impeller, even where stresses were reported to be higher by finite element analysis. The hardness of the impeller was 32 HRC, which was within the reported specification of 28 to 33 HRC. Ea sports f1 manager patch. Background: Two 17-4 PH stainless steel impeller blade specimens were submitted for metallurgical analysis. The specimens were pieces of impeller blades that exhibited crack-like indications on, at, or near the toe of an assembly weld (blade-to-hub weld) along the leading edge of the blade. The impeller was previously found to have crack-like indications during in-service magnetic particle testing (MT) inspection in November 2008.
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