Failure Investigation of an AlSi9Cu3 Alloy Die-Cast Cavity Insert

Two separately failed electrical connector pieces during a vibration test were received for failure analysis. Chemical composition, hardness values and microstructures of the each of the connector material indicate that the material of construction is a die cast aluminium-silicon type of alloy, closely matching with the standard ANSI/AA B380 alloy. Intergranular and faceted fracture features are observed and failure mechanism is found to be fatigue dominated. The connectors failed by impact fatigue arising out of the loosening of the connector assembly. This has happened by cavity formation and/or growth related microstructural degradation processes. Initial casting pores as well as microstructural degradations such as interconnected pores have developed in service and their successive growth, decohesion and interconnection of each of primary Si particles and Al-Fe-Mn precipitates (along precipitate-matrix interface) have led the initiation of the crack under fatigue loading. Brittle as-cast microstructure (as typified by the precipitate-matrix interfacial cracking), existing vibratory loading and absence of any rise in temperature in the system have assisted the initial cavity (crack) formation and/or growth. Moreover, initial fitment related looseness is an additional factor in initiating and propagating this damaging mechanism.

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Qualitative assessment of equipment failure cause finding and removal

MINING INFORMATIONAL AND ANALYTICAL BULLETIN ◽

10.25018/0236-1493-2018-12-64-116-126 ◽

2018 ◽

pp. 116-126

Author(s):

E. A. Vakulin ◽

A. I. Zayats ◽

V. A. Beklemeshev ◽

V. A. Ivashkevich ◽

V. A. Khazhiev ◽

...

Keyword(s):

Production Condition ◽

Real Life ◽

Open Pit Mine ◽

Qualitative Assessment ◽

Open Pit ◽

Quality Level ◽

Equipment Failure ◽

Operation Conditions ◽

Failure Investigation

Investigation of failures is one of the critical activities of mining and haulage equipment operability assurance in mining. Maintaining failure investigation at the required quality level, it is possible to identify provisions, rules and procedures that should be revised or changed, operation conditions that should be improved, additional personnel training, if required, etc. Investigation of failures in mines is under responsibility of machine men and electricians of maintenance and operation services. In reality, factory management and setup for production condition weak concernment of these workers in quality investigation aimed at finding of sources of equipment failures. This article describes real-life results achieved in development and use of maintenance service operation, technology and management monitoring. The requirements are substantiated for quality improvement in failure cause finding and removal in mining and haulage equipment at Chernogorsky open pit mine, SUEK-Khakassia. Causes of the present quality of failure investigation by machine men of Chernogorsky Repair and Engineering Works and Chernogorsky open pit mine are revealed. The proposed recommended practices will improve quality of mining and haulage equipment failure investigation.

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Microstructure of die-cast alloys Mg–Zn–Al(–Ca): a study by electron microscopy and small-angle neutron scattering

Zeitschrift für Metallkunde ◽

10.3139/146.030564 ◽

2003 ◽

Vol 94 (5) ◽

pp. 564-571 ◽

Cited By ~ 4

Author(s):

Michael Vogel ◽

Oliver Kraft ◽

Peter Staron ◽

Helmut Clemens ◽

Rainer Rauh ◽

...

Keyword(s):

Electron Microscopy ◽

Neutron Scattering ◽

Small Angle ◽

Small Angle Neutron Scattering ◽

Die Cast ◽

Cast Alloys

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Metallurgical Failure Investigation of a Surface Hardened Drive Shaft Made of Tempered Low-Alloy Steel 25CrMo4 (1.7218)

Practical Metallography ◽

10.3139/147.110395 ◽

2016 ◽

Vol 53 (9) ◽

pp. 592-598

Author(s):

B. Fischer ◽

E. Cagliyan

Keyword(s):

Alloy Steel ◽

Drive Shaft ◽

Low Alloy Steel ◽

Failure Investigation

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Failure Investigation of an Airline Engine Failure During Take Off

Practical Metallography ◽

10.3139/147.110270 ◽

2013 ◽

Vol 50 (12) ◽

pp. 821-830

Author(s):

K. Andersson ◽

R. Pederson ◽

B. Pettersson ◽

U. Klement

Keyword(s):

Failure Investigation ◽

Engine Failure

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Metallurgical Failure Investigation of Overheated and Fractured Investment Cast Nickel-base Bolts Made of Inconel 939

Practical Metallography ◽

10.3139/147.110255 ◽

2013 ◽

Vol 50 (7) ◽

pp. 501-512

Author(s):

S. Leggemann ◽

E. Cagliyan ◽

S. Riesenbeck ◽

A. Neidel

Keyword(s):

Failure Investigation ◽

Investment Cast ◽

Nickel Base

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DHA-WORLD

Alloy Digest ◽

10.31399/asm.ad.ts0697 ◽

2011 ◽

Vol 60 (5) ◽

Keyword(s):

Physical Properties ◽

Heat Treating ◽

High Hardenability ◽

High Toughness ◽

Die Cast

Abstract DHA-World is die cast and forging steel with high hardenability and high toughness for general use. This datasheet provides information on physical properties, and hardness. It also includes information on heat treating and machining. Filing Code: TS-697. Producer or source: International Mold Steel Inc..

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Failure Localization in a Multistage S-Band Power Amplifier

ISTFA 2016: Conference Proceedings from the 42nd International Symposium for Testing and Failure Analysis ◽

10.31399/asm.cp.istfa2016p0373 ◽

2016 ◽

Author(s):

Clarence Rebello ◽

Ted Kolasa ◽

Parag Modi

Keyword(s):

Output Power ◽

Power Amplifier ◽

Fault Tree ◽

Root Cause ◽

Failure Investigation ◽

Band Power ◽

Cause Of Failure ◽

Design Materials ◽

Board Level ◽

Failure Localization

Abstract During the search for the root cause of a board level failure, all aspects of the product must be revisited and investigated. These aspects encompass design, materials, and workmanship. In this discussion, the failure investigation involved an S-Band Power Amplifier assembly exhibiting abnormally low RF output power where initial troubleshooting did not provide a clear cause of failure. A detailed fault tree drove investigations that narrowed the focus to a few possible root causes. However, as the investigation progressed, multiple contributors were eventually discovered, some that were not initially considered.

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ZA-12

Alloy Digest ◽

10.31399/asm.ad.zn0049 ◽

1990 ◽

Vol 39 (5) ◽

Keyword(s):

Fracture Toughness ◽

Corrosion Resistance ◽

Shear Strength ◽

Die Casting ◽

Casting Alloys ◽

Die Cast ◽

The Family ◽

Aluminum Smelting ◽

Cold Chamber ◽

Intermediate Member

Abstract ZA-12 is the intermediate member of the family of three ZA die-casting alloys. Its melting point, solidification range and recommended casting-temperature range are greater than those of ZA-8. (See Alloy Digest Zn-48, January 1990). Due to these factors, ZA-12 must be die cast in cold chamber die-casting machines like conventional aluminum die-casting alloys. This datasheet provides information on composition, physical properties, hardness, elasticity, tensile properties, and compressive and shear strength as well as fracture toughness and fatigue. It also includes information on corrosion resistance as well as forming, machining, and surface treatment. Filing Code: Zn-49. Producer or source: Aluminum Smelting and Refining Company Inc.. See also Alloy Digest Zn-31, September 1977.

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