Impingement-Corrosion Failure of a Ferritic Malleable Iron Elbow

Water pipe of 4.5” diameter and has been operated for 8 year having failure due to corrosion attack on its external and internal surface. It is conducted failure analysis to find out the cause of corrosion by having testing examination of visual fractography, metalography,, SEM EDAX, hardness and chemical composition. Testing and examination results show that the failure / corroded pipe has a for in of general corrosion on the external surface due to environment factor or ground factor arround the pipe and on the internal surface was influenced by excessive root weld creating protrude which then causing turbolens and deposite to accelerate corrosion attack.Pipa berdiameter 4.5” yang berfungsi mengalirkan air bersih dan telah beroperasi selama 8 tahun, terjadi kerusakan berbentuk korosi pada permukaan luar pipa dan permukaan dalam. Untuk itu dilakukan analisa kerusakan untuk mengetahui penyebab terjadinya korosi dengan pengujian dan pemeriksaan secara visual,Fractography, Metallography, SEM, EDAX, Uji Kekerasan dan Uji Komposisi Kimia. Hasil pemeriksaan dan pengujian pada pipa yang rusak / korosi berbentuk jenis general korosi pada permukaan luar pipa yang diakibatkan faktor lingkungan atau tanah disekitar pipa, sedangkan pada bagian dalam pipa dipengaruhi oleh adanya lelehan pengelasan yang kurang sempurna sehingga menimbulkan benjolan yang mengakibatkan aliran air didalam pipa tidak lancar sehingga terjadi turbolensi yang menimbulkan endapan dan mengakibatkan percepatan terjadinya korosi.Keywords: Pipe, environtment, turbolens, corrosion, failure

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BELMALLOY

Alloy Digest ◽

10.31399/asm.ad.ci0006 ◽

1954 ◽

Vol 3 (2) ◽

Keyword(s):

Fracture Toughness ◽

Shear Strength ◽

Physical Properties ◽

Tensile Properties ◽

Heat Treating ◽

High Grade ◽

Malleable Iron ◽

Shock Resistance ◽

High Torque

Abstract BELMALLOY is a high grade pearlitic malleable iron providing rigidity and shock resistance to high torque loads. This datasheet provides information on composition, physical properties, hardness, elasticity, tensile properties, and shear strength as well as fracture toughness. It also includes information on heat treating, machining, and joining. Filing Code: CI-6. Producer or source: Belle City Malleable Iron Company.

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PEARLITIC MALLEABLE IRON

Alloy Digest ◽

10.31399/asm.ad.ci0026 ◽

1959 ◽

Vol 8 (3) ◽

Keyword(s):

Fracture Toughness ◽

Corrosion Resistance ◽

Shear Strength ◽

Cast Iron ◽

Physical Properties ◽

Tensile Properties ◽

High Strength ◽

Heat Treating ◽

Malleable Iron

Abstract PEARLITIC MALLEABLE IRON is a high strength cast iron recommended for dependable service, strength and machinability in highly stressed parts at work in mobile and stationary mechanisms. 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 heat treating, machining, and joining. Filing Code: CI-26. Producer or source: Albian Malleable Iron Company.

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An Overview of Cu Wire Intermetallic Compound Formation and a Corrosion Failure Mechanism

ISTFA 2012: Conference Proceedings from the 38th International Symposium for Testing and Failure Analysis ◽

10.31399/asm.cp.istfa2012p0310 ◽

2012 ◽

Author(s):

Dongmei Meng ◽

Laura Buck ◽

James Cargo

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Corrosion Mechanism ◽

Fundamental Study ◽

Corrosion Failure ◽

Transmission Electron ◽

Intermetallic Compound Formation ◽

Scanning Transmission ◽

Low K

Abstract Cu needs a higher level of ultrasound combined with bonding force to be bonded to the Al pad properly, not just because Cu is harder than Au, but it is also harder to initiate intermetallic compounds (IMC) formation during bonding. This increases the chances of damaging the metal/low k stack under the bondpad. This paper presents a fundamental study of IMC as well as one example of a failure mode of Cu/Al bonded devices, all based on detailed analysis using scanning electron microscopy, scanning transmission electron microscopy, energy dispersive spectrometers, and transmission electron microscopy. It presents a case study showing a corrosion mechanism of Cu/Al ballbond after 168hr UHAST stress. It is observed that all Cu9Al4 was consumed, while very little copper aluminide remained after 168 hours of UHAST stressing.

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