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Article
Publication date: 1 February 2013

Xin Luo, Wenhui Du, Xiuzhen Lu, Toshikazu Yamaguchi, Gavin Jackson, Li lei Ye and Johan Liu

The composition and thickness of surface oxide of solder particles is extremely important to the quality of interconnect and reliability of packaged system. The purpose of…

Abstract

Purpose

The composition and thickness of surface oxide of solder particles is extremely important to the quality of interconnect and reliability of packaged system. The purpose of this paper is to develop an observable measurement to research the issue.

Design/methodology/approach

AES (Auger electron spectroscopy), XPS (X‐ray photoelectron spectroscopy), TEM (transmission electron microscopy) and STEM (scanning transmission electron microscopy) were employed to examine the oxide layer on microscale solder powders. Conventional techniques and FIB (Focus Ion Beam) were employed for the TEM sample preparation. High angle annular dark field (HAADF) pattern was applied to distinguish the oxide layer and the solder matrix by the contrast of average atomic number. The results were confirmed by AES and XPS measurement.

Findings

The solder powders were exposed to air (70% relative humidity) at 150°C for 0, 120 and 240 h for the accelerated growth of oxide. The surface oxide thickness was 6 nm and 50 nm measured by TEM for 0 h and 120 h samples, respectively. It was found that the increase in surface oxide thickness of solder particles is proportional to the rooting of time. The elemental distribution along the oxide was quantified by line scanning using STEM and the atomic ratio of Sn to O in the oxide layer nearer to the outer, the middle, and the inner (adjacent to the solder matrix) was found to be 1:2, 2:3 and 1:1, respectively. The result was validated using XPS which gave Sn to O ratio of 1:2 at 5 nm depth of surface oxide.

Originality/value

This is the first time FIB technology has been used to prepare TEM specimens for solder particles and TEM pictures shown of their surface oxide layer. Though requiring more care in sample preparation, the measurements by TEM and STEM are believed to be more direct and precise.

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Article
Publication date: 1 January 1989

Wayne L. Gindrup

The most reliable, inexpensive, and trouble‐free shielding method known at the present is spray coating using paints containing conductive metal particles. The best metals…

Abstract

The most reliable, inexpensive, and trouble‐free shielding method known at the present is spray coating using paints containing conductive metal particles. The best metals are those which do not lose conductivity due to oxidation. These consist of gold, platinum, palladium, iridium, silver and osmium. The least expensive is silver. A coating containing fine silver particles is an excellent conductor and shield. Paints containing fine silver particles have been available a long time but are very happy and very expensive. Their performance is, however, excellent.

Details

Pigment & Resin Technology, vol. 18 no. 1
Type: Research Article
ISSN: 0369-9420

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Article
Publication date: 19 July 2019

Alagarsamy S.V. and Ravichandran M.

Aluminium and its alloys are the most preferred material in aerospace and automotive industries because of their high strength-to-weight ratio. However, these alloys are…

Abstract

Purpose

Aluminium and its alloys are the most preferred material in aerospace and automotive industries because of their high strength-to-weight ratio. However, these alloys are found to be low wear resistance. Hence, the incorporation of ceramic particles with the aluminium alloy may be enhanced the mechanical and tribological properties. The purpose of this study is to optimize the specific wear rate and friction coefficient of titanium dioxide (TiO2) reinforced AA7075 matrix composites. The four wear control factors are considered, i.e. reinforcement (Wt.%), applied load (N), sliding velocity (m/s) and sliding distance (m).

Design/methodology/approach

The composites were fabricated through stir casting route with varying weight percentages (0, 5, 10 and 15 Wt.%) of TiO2 particulates. The mechanical properties of the composites were studied. The specific wear rate and friction coefficient of the newly prepared composites was determined by using a pin-on-disc apparatus under dry sliding conditions. Experiments were planned as per Taguchi’s L16 orthogonal design. Signal-to-noise ratio analysis was used to find the optimal combination of parameters.

Findings

The mechanical properties such as yield strength, tensile strength and hardness of the composites significantly improved with the addition of TiO2 particles. The analysis of variance result shows that the applied load and reinforcement Wt.% are the most influencing parameters on specific wear rate and friction coefficient during dry sliding conditions. The scanning electron microscope morphology of the worn surface shows that TiO2 particles protect the matrix from more removal of material at all conditions.

Originality/value

This paper provides a solution for optimal parameters on specific wear rate and friction coefficient of aluminium matrix composites (AMCs) using Taguchi methodology. The obtained results are useful in improving the wear resistance of the AA7075-TiO2 composites.

Details

Industrial Lubrication and Tribology, vol. 71 no. 9
Type: Research Article
ISSN: 0036-8792

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Article
Publication date: 1 July 2006

D.D. Hillman and L.S. Chumbley

To evaluate the oxide formation characteristics of tin (Sn) as a function of conditioning treatment and define a conditioning methodology that rapidly produces a tin oxide…

Abstract

Purpose

To evaluate the oxide formation characteristics of tin (Sn) as a function of conditioning treatment and define a conditioning methodology that rapidly produces a tin oxide thickness and oxide species morphology similar to those formed in ambient oxidation.

Design/methodology/approach

Electrochemical reduction analysis and scanning electron microscopy techniques were utilized to identify tin oxide species and oxide quantities on tin samples which were subjected to a variety of conditioning methodologies.

Findings

Tin oxide species were identified and oxide quantities measured. Comparisons of tin oxide species/quantities were completed for the different conditioning methodologies used and for other industry oxide investigations. The following conclusions were reached: all conditioning methodologies produced both SnO and SnO2 tin oxide species; steam conditioning produced the thickest oxides; the conditioning methodologies investigated were found to produce oxide thicknesses similar to those formed under ambient conditions.

Research limitations/implications

Further investigation would be beneficial using this study as a foundation. Additional conditioning methodologies and a larger selection of various tin surfaces would provide a future understanding of the impact of oxide species and thickness on solderability.

Practical implications

The electronics industry has attempted to “predict” a surface's susceptibility to oxidation by using accelerated conditioning techniques. An understanding of the formation of tin oxidation products created by accelerated conditioning techniques could be highly beneficial to the electronics industry. The standardization and use of a realistic accelerated conditioning technique would reduce testing cycle time, increase the predictability and consistency of test results, and lower testing costs.

Originality/value

This paper was incorporated into an original electronics manufacturer's solderability testing/analysis procedures, and the results are being utilized by the electronics industry solderability specification task groups/committees.

Details

Soldering & Surface Mount Technology, vol. 18 no. 3
Type: Research Article
ISSN: 0954-0911

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Article
Publication date: 10 December 2019

Yongliang Jin, Jian Li, Bingxue Cheng, Dan Jia, Jiesong Tu, Shengpeng Zhan, Lian Liu and Haitao Duan

This paper aims to investigate the thermal oxidation behavior of trimethylolpropane trioleate (TMPTO) base oil when exposed to Fe surfaces.

Abstract

Purpose

This paper aims to investigate the thermal oxidation behavior of trimethylolpropane trioleate (TMPTO) base oil when exposed to Fe surfaces.

Design/methodology/approach

Samples of TMPTO bulk oil were placed in Fe vessels and heated in an oven to accelerate the oxidation at different time intervals, while others were placed in glass vessels and used as experimental controls. Subsequently, the physicochemical properties of the oxidized TMPTOs, including the kinematic viscosity and acid value, were measured and a structural analysis was conducted using the Raman and Fourier transform infrared (FTIR) techniques.

Findings

The results demonstrate that the TMPTO bulk oil exhibited an exponential increase in the kinematic viscosity along with the increasing acid value over the oxidation time. The Fe surface significantly increased the kinematic viscosity of TMPTO, while only mildly impacting its acid value compared with the experimental controls. The structural analysis results of the TMPTO suggest that the C = C and = C-H bonds were the vulnerable sites. Furthermore, the results suggest that the Fe surface evidently accelerates the chemical reactions of the C = C and the = C-H bonds, and less alcohols and more carbonyl products were identified in the oil samples that were heated in the Fe vessels.

Originality/value

The results demonstrate that the Fe surfaces affected the oxidation behavior of the TMPTO base oil, and an interaction mechanism between the Fe and the TMPTO is developed.

Details

Industrial Lubrication and Tribology, vol. 72 no. 3
Type: Research Article
ISSN: 0036-8792

Keywords

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Article
Publication date: 1 January 1976

P.L. Hurricks

The first part of this paper appeared in our November/December issue and dealt with fretting wear behaviour of mild steel from room temperature to 600°C in air. The…

Abstract

The first part of this paper appeared in our November/December issue and dealt with fretting wear behaviour of mild steel from room temperature to 600°C in air. The general mechanism for fretting is discussed at all temperatures where normal oxidative processes become involved. The nature of fretting wear is also covered and the effects of temperature are described. In this part of the paper, the discussion is continued to include triboxidation, delamination theory, atmospheric environment, transition temperatures, activitation energy and other factors affecting the influence of temperature on fretting.

Details

Industrial Lubrication and Tribology, vol. 28 no. 1
Type: Research Article
ISSN: 0036-8792

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Article
Publication date: 19 May 2020

Jialin Yang, Yunting Guo, Wei Zai, Siyuan Ma, Liang Dong and Guangyu Li

This paper aims to find a way to improve the surface insulation, corrosion resistance and mechanical properties of Fe-Cr-Al electrothermal alloy, exploring the best…

Abstract

Purpose

This paper aims to find a way to improve the surface insulation, corrosion resistance and mechanical properties of Fe-Cr-Al electrothermal alloy, exploring the best oxidation condition and analyzing the oxidation mechanism.

Design/methodology/approach

Electrochemical workstation was used for anodic oxidation, and the effect of current density, ethylene glycol concentration and oxidation time on properties of the film were investigated by resistivity test, scanning electron microscope, electrochemical tests (potentiodynamic polarization and electrochemical impedance spectroscopy) and mechanical tests, and the oxidation process was analyzed by X-ray photoelectron spectroscopy (XPS).

Findings

According to the potential-time curves of anodic oxidation and the analysis of XPS, the whole oxidation process can be divided into four stages. When the current density is 0.8 A/dm2, the ethylene glycol concentration is 10%, and the oxidation time is 60 min, the film has the best corrosion protection, mechanical properties and surface morphology. The resistivity of the samples is about 13 orders magnitude than that of the matrix.

Originality/value

In this paper, a protective electrically insulating film was prepared by anodic oxidation in an alkaline electrolyte solution. The oxidation conditions were optimized and the oxidation mechanism was analyzed.

Details

Anti-Corrosion Methods and Materials, vol. 67 no. 4
Type: Research Article
ISSN: 0003-5599

Keywords

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Article
Publication date: 19 July 2019

Bingxue Cheng, Haitao Duan, Yongliang Jin, Lei Wei, Jia Dan, Song Chen and Jian Li

This paper aims to investigate the thermal oxidation characteristics of the unsaturated bonds (C=C) of trimethylolpropane trioleate (TMPTO) and to reveal the high…

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Abstract

Purpose

This paper aims to investigate the thermal oxidation characteristics of the unsaturated bonds (C=C) of trimethylolpropane trioleate (TMPTO) and to reveal the high temperature oxidation decay mechanism of unsaturated esters and the nature of the anti-oxidation properties of the additives.

Design/methodology/approach

Using a DXR laser microscopic Raman spectrometer and Linkam FTIR600 temperature control platform, the isothermal oxidation experiments of TMPTO with or without 1.0 wt. % of different antioxidants were performed.

Findings

The results indicated that the Raman peaks of =C-H, C=C and -CH2- weaken gradually with prolonged oxidation time, and the corresponding Raman intensities drop rapidly at higher temperatures. The aromatic amine antioxidant can decrease the attenuation of peak intensity, as it significantly reduces the rate constant of C=C thermal oxidation. The hindered phenolic antioxidant has a protective effect during the early stages of oxidation (induction period), but it may accelerate the oxidation of C=C afterwards.

Originality/value

Research on the structure changes of synthetic esters during oxidation by Raman spectroscopy will be of great importance in promoting the use of Raman spectroscopy to analyze the oxidation of lubricants.

Details

Industrial Lubrication and Tribology, vol. 71 no. 5
Type: Research Article
ISSN: 0036-8792

Keywords

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Article
Publication date: 21 March 2008

Manpreet Kaur, Harpreet Singh and Satya Prakash

This paper seeks to summarise the results of available research on the use of high velocity oxy‐fuel (HVOF) thermal‐spray technique to provide protection against high…

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1353

Abstract

Purpose

This paper seeks to summarise the results of available research on the use of high velocity oxy‐fuel (HVOF) thermal‐spray technique to provide protection against high temperature corrosion and erosion‐corrosion of materials.

Design/methodology/approach

This paper describes one of the recent thermal‐spray processes, namely HVOF thermal‐spray technology and presents a survey of the studies on the use of this technique to provide protection against corrosion and erosion‐corrosion of high temperature alloys, with a special emphasis on boiler steels.

Findings

High temperature corrosion and erosion‐corrosion are serious problems observed in steam‐powered electricity generation plants, gas turbines, internal combustion engines, fluidized bed combustors, industrial waste incinerators and recovery boilers in paper and pulp industries. These problems can be prevented by changing the material or altering the environment, or by separating the component surface from the environment. Corrosion prevention by the use of coatings for separating materials from the environment is gaining importance in surface engineering. Amongst various surface modifying techniques, thermal spraying has developed relatively rapidly due to the use of advanced coating formulations and improvements in coating application technology. One of the variants of thermal spraying, namely HVOF has gained popularity in recent times due to its flexibility for in‐situ applications and superior coating properties.

Research limitations/implications

This review covers mainly information that has been reported previously in the open literature, international journals and some well‐known textbooks.

Practical implications

The paper presents a concise summary of information for scientists and academics, planning to start their research work in the area of surface engineering.

Originality/value

This paper fulfils an identified information/resources need and offers practical help to an individual starting out on a career in the area of surface engineering for erosion‐corrosion and wear.

Details

Anti-Corrosion Methods and Materials, vol. 55 no. 2
Type: Research Article
ISSN: 0003-5599

Keywords

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Article
Publication date: 3 February 2021

Abdul Rehman, Mohammad Hassan Shirani Bidabadi, Liang Yang, Zheng Yu, Chen Hao, Chi Zhang and Zhigang Yang

This study aims to optimise the effect of pre-oxidation on hot corrosion behaviour of Tribaloy T-900 at 900 °C in mixed Na2SO4 and K2SO4.

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Abstract

Purpose

This study aims to optimise the effect of pre-oxidation on hot corrosion behaviour of Tribaloy T-900 at 900 °C in mixed Na2SO4 and K2SO4.

Design/methodology/approach

Prior to hot corrosion experiment, pre-oxidation treatments were carried in ambient air at 900 °C for 1, 5 and 10 h, respectively. The hot corrosion experiments were performed in a box type furnace at 900 °C. Both surfaces of specimens were brushed with saturated salt solution of 75 wt.% Na2SO4 + 25 wt.% K2SO4. After brushing, the salt-coated specimens were placed in electric stove to ensure drying of salt. After drying, presence of 3 mg/cm2 salt on specimen’s surface was ensured through weighting.

Findings

The 1-h pre-oxidation treatment prior to hot corrosion showed superior hot corrosion resistance against molten salt attack. An optimum pre-oxidation time of 1 h helped timely formation of protective Cr2O3 layer and inhibited the formation of less stable and porous surface oxides of Ni and Mo during hot corrosion.

Originality/value

Pre-oxidation effect on hot corrosion behaviour of refractory metal (such as Mo in investigated alloy) containing alloy has never been reported previously. Refractory metals oxide (e.g. MoO3) could transform the corrosion phenomena to catastrophic failure through acidic fluxing.

Details

Anti-Corrosion Methods and Materials, vol. 68 no. 1
Type: Research Article
ISSN: 0003-5599

Keywords

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