scholarly journals RESTORATION OF PARTS MADE OF STEEL EI961-SH BY ELECTROLYTIC CHROME PLATING

2015 ◽  
pp. 112-116 ◽  
Author(s):  
I. M. Kovenski ◽  
S. V. Malysh
Keyword(s):  
Surface Structure ◽  
Electromotive Force ◽  
Surface Preparation ◽  
Thermal Electromotive Force ◽  
Chrome Plating

The influence of the surface structure on the quality of chrome plating was studied. It was found that the quality of electrolytic plating depended on a difference in the thermo-e.m.f. value on the surface of the recovered part. A method was proposed for assessing the quality of the surface preparation prior to electroplating by measuring the thermal electromotive force.

scholarly journals STRUCTURAL PECULIARITIES OF THE PROCESS OF ELECTROLYTIC CHROMIUM PLATING IN RESTORATION OF WORN PARTS

2018 ◽  
pp. 92-97
Author(s):  
I. M. Kovenskiy ◽  
S. V. Malysh ◽  
V. V. Povetkin
Keyword(s):  
Surface Preparation ◽  
Inhomogeneous Structure ◽  
Band Theory ◽  
Electrolytic Chromium ◽  
Chrome Plating ◽  
Chromium Plating ◽  
Thermal Emf ◽  
Structural Peculiarities ◽  
Similarity Of Processes

Processes occurring at the metal-electrolyte interface in chrome plating of parts with an inhomogeneous structure have been considered from the standpoint of the band theory of semiconductors. Similarity of processes in the systems metal - semiconductor and metal - electrolyte has been established. A technique for estimating the quality of surface preparation of worn parts for electrolytic chromium plating based on the results of measuring the spread of thermal EMF values has been validated.

EELS characterization of “Smut” layer films on steel surface prepared for chrome plating by anodic etching

1995 ◽  
Vol 53 ◽  
pp. 538-539
Author(s):  
E Y. Wang ◽  
J. T. Cherian ◽  
A. Madsen ◽  
R. M. Fisher
Keyword(s):  
Steel Surface ◽  
Surface Preparation ◽  
Treatment Method ◽  
Chrome Plating ◽  
Transmission Electron ◽  
Alloy Steels ◽  
Pre Treatment ◽  
Hard Chrome ◽  
Electron Energy Loss

Many steel parts are electro-plated with chromium to protect them against corrosion and to improve their wear-resistance. Good adhesion of the chrome plate to the steel surface, which is essential for long term durability of the part, is extremely dependent on surface preparation prior to plating. Recently, McDonnell Douglas developed a new pre-treatment method for chrome plating in which the steel is anodically etched in a sulfuric acid and hydrofluoric acid solution. On carbon steel surfaces, this anodic pre-treatment produces a dark, loosely adhering material that is commonly called the “smut” layer. On stainless steels and nickel alloys, the surface is only darkened by the anodic pre-treatment and little residue is produced. Anodic pre-treatment prior to hard chrome plating results in much better adherence to both carbon and alloy steels.We have characterized the anodic pre-treated steel surface and the resulting “smut” layer using various techniques including electron spectroscopy for chemical analysis (ESCA) on bulk samples and transmission electron microscopy (TEM) and electron energy-loss spectroscopy (EELS) on stripped films.

Dry Surface Preparation Using Supercritical Cryogenic Nitrogen Jet Improves the Adhesion Strength of Cold Gas Sprayed Coatings (SCNCS)

2018 ◽  
Vol 941 ◽  
pp. 1668-1673
Author(s):  
Abdel Tazibt ◽  
Guillaume Ezo'o ◽  
Yosri Khalsi ◽  
Mustapha Yahiaoui
Keyword(s):  
Surface Preparation ◽  
Cold Spraying ◽  
Substrate Preparation ◽  
Preparation Methods ◽  
Adhesion Performance ◽  
Pulsed Water Jet ◽  
Sprayed Coating ◽  
Sprayed Coatings ◽  
Required Quality

The adhesion performance of Cold Sprayed coatings depends on the quality of the substrate [1,2,4,8]. Before deposition, the surface of substrate must be prepared to a specific required quality, which promotes the anchoring of sprayed coating. Grit Blasting (Samson et al.) [1] is known as the conventional surface preparation before Cold Spraying. But such method causes issues: a) shallow roughness, which does not strengthen bonds between layer and substrate; b) embedment of particles in the substrate, which creates discontinuity of the material at the interface and causes cracks that degrade the layer. Recently, Laser [2] and Pulsed Water Jet (PWJ) [1] have been tested as substrate preparation methods. These methods have shown their ability to generate improved roughness without particle embedment. PWJ has particularly shown interest in Al substrate to generate crevices, which are anchors for the Cold Sprayed coatings. Nevertheless, Laser affects thermally the substrate and induces constraints that may disadvantage the coating quality. PWJ generates liquid effluents. Besides some substrates such as ferrous metals can react with oxygen of water leading to corrosion and coating adhesion weakness.

High Quality Hydrothermal ZnO Crystals

1998 ◽  
Vol 537 ◽  
Author(s):  
M. Suscavage ◽  
M. Harris ◽  
D. Bliss ◽  
P. Yip ◽  
S.-Q. Wang ◽  
...  
Keyword(s):  
Zinc Oxide ◽  
Liquid Helium ◽  
Room Temperature ◽  
Surface Preparation ◽  
Critical Factor ◽  
High Quality ◽  
Rocking Curve ◽  
X Ray ◽  
Oxide Crystals

AbstractZinc Oxide crystals have historically been grown in hydrothermal autoclaves with a basic mineralizer; however, doubts have been raised about the quality of such crystals because they have often exhibited large x-ray rocking curve widths and low photoluminescence (PL) yield with large linewidths. Several ZnO crystals were grown hydrothermally and sliced parallel to the c-plane. This resulted in opposite surfaces (the C+ and C-) exhibiting pronounced chemical and mechanical differences. Different surface treatments were investigated and compared by PL both at room temperature and liquid helium temperatures, and by double axis X-ray rocking curve measurements. The high quality of hydrothermally-grown ZnO is substantiated by the narrow rocking curve widths and sharp PL peaks obtained. A critical factor in obtaining these results was found to be surface preparation.

scholarly journals Antithesis and argument in the hymns of Ephrem the Syrian

1988 ◽  
Vol 44 (3) ◽  
Author(s):  
P. J. Botha
Keyword(s):  
Surface Structure ◽  
Semantic Structure ◽  
Church Father ◽  
Ephrem The Syrian

This paper reflects research on the semantic structure of antitheses. The thesis being proposed is that the defining quality of antitheses was implemented by the Syrian church father Ephrem as a rhetoric technique to enhance the power of arguments in his hymns. Examples are being investigated to explain the function of antitheses in the surface structure of some of his arguments.

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