Tarnish resistance, corrosion and stress corrosion cracking of gold alloys

Rapson, W. H.

doi:10.1007/bf03215466

Cited by 18 publications

(29 citation statements)

References 7 publications

(10 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…For simple Au-Cu alloys, the existence of four phases are possible, namely α (Au, Cu) solid solution, Au 3 Cu, AuCu and AuCu 3 intermetallics [17]. Given that the percentage of Cu in the alloys in this study lies between 42 and 51 %, α (Au, Cu) and AuCu are the most likely phases to be present and possibly Au 3 Cu.…”

Section: Atomic Absorption Spectroscopy Analysis Of Gold Alloysmentioning

confidence: 87%

“…Selective dissolution of homogeneous binary Au-Ag and Au-Cu alloys has been studied in detail [3]. Mechanisms for attack of the selective dissolution of the more active atoms (alloying species) is influenced by a number of factors to include (1) the activation energy or overpotential to remove these species; (2) presence of these atoms within the lattice, for example at kink sites where removal of atoms is easier and (3) migration of lattice vacancies and diffusion of the more noble species (gold) to form clusters/islands.…”

Section: Atomic Absorption Spectroscopy Analysis Of Gold Alloysmentioning

confidence: 99%

“…For example the preferential corrosion of Ni-rich phases containing less gold in Ni-based white gold alloys, may occur when exposed to acid. It was further stated [3] that while this form of corrosion may occur due to the presence of heterogeneous phases in ternary, low caratage Au-Ag-Cu alloys, no studies have been reported of this effect in quaternary Au-Ag-Cu-Zn alloys (Fig. 9).…”

Section: Atomic Absorption Spectroscopy Analysis Of Gold Alloysmentioning

confidence: 99%

“…Rapson [3] has reported that the significant areas where corrosion and tarnishing of gold alloys becomes important are (1) tarnishing of gold electrical contacts and gold jewellery; (2) corrosion of gold dental alloys and gold jewellery and (3) stress corrosion cracking of gold jewellery. Gold jewellery is known to corrode in a number of environments which include sea water and chlorinated water.…”

Section: Introductionmentioning

confidence: 99%

“…Numerous studies have been conducted on the mechanisms and consequential effects of stress corrosion cracking (SCC), a well-known form of environmental attack in low carat gold jewellery, particularly below 14 carat gold content [3][4][5][6][7][8][9][10]. While there appears to be less information available on other forms of corrosion, such as pitting and intergranular corrosion, the concepts of selective leaching of alloying elements to modify alloys for decorative purposes has been around for many years [11,12].…”

Section: Introductionmentioning

confidence: 99%

See 4 more Smart Citations

The electrochemical corrosion behaviour of quaternary gold alloys when exposed to 3.5 % NaCl solution

2013

View full text Add to dashboard Cite

Lower carat gold alloys, specifically 9 carat gold alloys, containing less than 40 % gold, and alloying additions of silver, copper and zinc, are commonly used in many jewellery applications, to offset high costs and poor mechanical properties associated with pure gold. While gold is considered to be chemically inert, the presence of active alloying additions raises concerns about certain forms of corrosion, particularly selective dissolution of these alloys. The purpose of this study was to systematically study the corrosion behaviour of a series of quaternary gold-silvercopper-zinc alloys using dc potentiodynamic scanning in saline (3.5 % NaCl) environment. Full anodic/cathodic scans were conducted to determine the overall corrosion characteristics of the alloy, followed by selective anodic scans and subsequent morphological and compositional analysis of the alloy surface and corroding media to determine the extent of selective dissolution. Varying degrees of selective dissolution and associated corrosion rates were observed after anodic polarisation in 3.5 % NaCl, depending on the alloy composition. The corrosion behaviour of the alloys was determined by the extent of anodic reactions which induce (1) formation of oxide scales on the alloy surface and or (2) dissolution of Zn and Cu species. In general, the improved corrosion characteristics of alloy #3 was attributed to the composition of Zn/Cu in the alloy and thus favourable microstructure promoting the formation of protective oxide/chloride scales and reducing the extent of Cu and Zn dissolution.

show abstract

Section: Atomic Absorption Spectroscopy Analysis Of Gold Alloysmentioning

confidence: 87%

Section: Atomic Absorption Spectroscopy Analysis Of Gold Alloysmentioning

confidence: 99%

Section: Atomic Absorption Spectroscopy Analysis Of Gold Alloysmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

The electrochemical corrosion behaviour of quaternary gold alloys when exposed to 3.5 % NaCl solution

2013

View full text Add to dashboard Cite

show abstract

Electroformed objects for jewelry: secondary ion mass spectrometry characterization of Au films from CN-free electrolytes

Fabrizio

Piccirillo

Daolio

1998

Rapid Commun. Mass Spectrom.

View full text Add to dashboard Cite

CN-free electrolytic baths were studied in order to deposit thick Au films on different cathodic substrates. Secondary ion mass spectrometry characterization of electrodeposited gold for jewelry is presented, analyzing surface composition and element distribution along the thickness. It was verified that additives used to improve the deposits are included in the coatings during the electrolysis. Cathodic substrates utilized for the electrodeposition were detected on the surface spectra, suggesting intermetallic diffusion along the deposits. #

show abstract

Tarnish and corrosion evaluation of a blue gold‐based alloy

Carvalho

Soares

Fonseca

et al. 2009

Materials & Corrosion

View full text Add to dashboard Cite

The use of some coloured gold alloys is dependent on the physical stability of the material when subjected to a corrosion media. This paper is concerned with the effect of two common detrimental environments (sweat and sulphuric solutions) on the stability of a blue gold-base alloy. Changes in physical properties, namely colour and brightness, were evaluated with time. It was observed that, for sulphuric solution, significant changes were obtained even for small immersion times. For the artificial sweat solution, changes occur, but the alloy is significantly more resistant. The alloy corrosion mechanisms are presented for both types of solutions. The products of corrosion were characterized by optical and SEM/EDS microscopy and by XPS spectroscopy. A comparison of the corrosion mechanisms, between the two immersion solutions, is also presented.

show abstract

Tarnish resistance, corrosion and stress corrosion cracking of gold alloys

Cited by 18 publications

References 7 publications

The electrochemical corrosion behaviour of quaternary gold alloys when exposed to 3.5 % NaCl solution

The electrochemical corrosion behaviour of quaternary gold alloys when exposed to 3.5 % NaCl solution

Electroformed objects for jewelry: secondary ion mass spectrometry characterization of Au films from CN-free electrolytes

Tarnish and corrosion evaluation of a blue gold‐based alloy

Contact Info

Product

Resources

About