Advanced Electro-Spark Deposition Process on Metallic Alloys

This chapter will study the material base-surface multilayer system for various types of depositions (increasing the wear resistance of Fe-C alloy parts) whose compatibility with the substrate provides high-quality parts. Thus, this system of layers can be applied on both the new and worn parts, being able to recondition and reintroduce in an intensive exploitation regime any parts with complex configuration operating in dynamic conditions. Deposited layers will be obtained using electro-spark deposition (ESD) process, which is a technology that uses electrical energy stored in a capacitor to initialize an electrical spark between the cathode and the anode. The high temperature generated by the electrical spark leads to partial melting of substrate and mixing of it with the material of the electrode. Between the two electric sparks, the amount of the molten metal solidifies to form the surface layer. The ESD is a very well used process for materials manufacturing in many industrial sectors

Hardening of the Grey Cast Iron through the Vibrating Electrode Method Using a WC Electrode and in Combination with TiC and Ti Electrode

There have been tested samples of grey cast iron, the hardening being made through WC coating through the vibrating electrode method with a layer, two layers and through double layers combined with Ti and TiC. Besides double layers combined there were also made triple combined layers. Afterwards there were taken photographs of macro-hardness and HV50 micro-hardness into the material in into the layer. There were also made rugosity measurements. Then in order to appreciate the internal stresses were made ring specimens type Naimov. On the exterior of these specimens were made coatings with the vibrating electrode

Studies Regarding the Properties Modification of AISI 310S Steel

The paper presents an analysis of classical heat treatments, which can be applied to AISI310S steel samples. The influence of these heat treatments was highlighted by micro-hardness measurements – Vickers method, and also the structural analysis made on electronic microscope, at different magnitudes. The AISI 310S steel is part of chrome-nickel stainless steels and presents good resistance properties. These properties are due to principal alloying elements (nickel, chrome) and recommend its being used in corrosive medium and high temperatures

The Influence of Waste Water Composition on the Pumping System Corrosion

Wastewater piping systems in urban agglomerations or industrial areas have problems with the wear and tear of equipment and water transport pipelines used. The problems are related to hydromechanics wear and corrosion due to the presence of solid particles transported with water and due to the residual chemical compounds resulting from industrial technological processes, as well as the presence of biological waste from domestic consumers. In the paper are presented the corrosive characteristics of the waste waters and a review of the effects of wear and corrosion in the case of submersible pumps is made

Analysis of Titanium Interface and Tungsten Exterior Layer Thickness Coated by Vibrator Electrode Method

The goal of this paper is to create metallic materials with superior functional performances. The layer obtained by electrode vibrator method must have a very good adherence on part surface and a high chemical and thermal compatibility with the substrate, as well as high ware and oxidation quality. So, in this paper Titan coating as interface and Wolfram as exterior layer were studied on ferito-perlitic cast-iron substrate. Pictures were taken with electronic scanning microscope

Study of Thermal Conductivity Variation Depending of the Heat Treatment for Tool Steels

This paper studied the influence of quenching and tempering steel structures on the thermal conductivity for OSC 11 steel. For the experiment we used samples that were subjected to heat treatment quenching and tempering at 200˚C and at 500˚C. To emphasize the structure and structural changes in both the sample and the untreated samples, micrographs and photos were made by scanning electron microscopy. Measured conductivity results were presented graphically and studied to highlight their influence on the hardening structure

Deposition Technologies for Obtaining Thin Films with Special Properties

The properties of metallic materials can be improved by deposition of materials. The coating has a tear strength and better hydro-abrasive corrosion. The thin layer deposition has a thickness of less than 10 micrometers. When speaking about deposition technologies, it is not just about deposited thin layers, but the whole assembly (layer / substrate), therefore the degree of adherence and the costs of making such a substrate have to be taken into account and the whole must be much more powerful than anything taken separately. In this paper we presented several methods of thin film deposition. We also highlighted some of the advantages and disadvantages of several deposition methods

Microstructural Analysis of Three Layer Depositions with Ni and Ti on Steel Using the EDS Method

The ESD method (electro spark deposition) is used to cover through deposition the active parts of machines, working in heavy abrasive wear moist environment as well as in a dry environment. The paper proposes the use ESD method for Fe-C alloys for obtaining thin layers system with physical-mechanical properties improved comparing to base material. Due to polar effect, the predominant transfer of anode’s material (electrode) towards cathode (piece) assures the forming of the superficial layer with well-determined physical - chemical properties. In addition, in multiple layers case the deposit of a supplementary layer emphasizes the diffusion of the first deposited layer by anchoring more the coating

New Trends in Bioactive Glasses for Bone Tissue: A Review

Bioactive glasses are very attractive materials, used for tissue engineering materials, usually to fill and restore bone defects. This category of biomaterials, show considerable potential for orthopaedic surgery because they can promote bone tissue regeneration. Many trace elements have been incorporated in the glass network, an example is metallic glasses to obtain the desired properties. Because of tolerable mechanical properties, and because they are able to bond to living bone and stimulate its regeneration, this bioactive glasses have a particular interest and are in a continuous research and improvement. The chapter presents the history of bioactive glasses, classification, include a summary of common fabrication methods, applications, surface coatings, applications and future trends in relation to human bone. This review highlight new trends and areas of future research for bioactive glasses

CORROSION AND WEAR OF WASTEWATER PUMPING SYSTEMS

The submersible pumps are submerged in the fluid that must be pumped, this type of pump is capable to push out large volumes of water. The watertight subassembly of this equipment includes a variable power engine that can be used for various household applications or industrial purposes. Wastewater transported by pumps corrodes and wear the transport system. The materials used for the construction of these pumps must withstand the acidity of the water, capitation phenomenon, the wear caused by the particles in the suspension and maintain their operating properties. The paper presents an analysis of the wear and corrosioneffects on the wastewater pumps and an analysis of the pump impeller material