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Textile industry is one of the promising industries in India. Textile machineries have a huge number of components that are subject to wear and tear. Replacement of the components is very expensive and may not produce break even in many cases. Coatings have been widely used on the mechanical components that are being used in the textile machinery. In this work, the wear characteristics of tungsten carbide coated steel specimens have been studied for probable application in the textile industry. For the purpose of coating, different coating techniques have been studied, among that HVOF technique and plasma coating technique have been extensively studied. In this work, plasma coating technique was used to coat the EN 8 steel specimens with tungsten carbide. The coatings were of varying thickness and different stand-off distance of the plasma torch was considered for the coating to see which would be the best coating thickness and the best stand-off distance. Using the pin on disc experimental set up, the specific wear rate was calculated and the friction coefficient was calculated. It was observed that the frictional force and the Co-efficient were the least in the case of the first experiment that is, at 4 in. stand-off distance and 100 µm coating thickness. SEM analysis and XRD analysis were done on the specimens for mechanical characterization and to ensure that the coatings are uniform and also to determine the composition of the coating.

Improvement of tribological property will enhance textile equipment’s efficiency, reliability, and economics and reduce system down time. The metals or alloys are protected against corrosion and wear by applying corrosion and wear resistant thermal spray coatings. EN8 material is an unalloyed medium carbon steel which possess high strength to weight ratio in comparison to that of the normal bright mild steel. In most of the textile industries, the rollers of the machines are made of EN19 material. Thermally sprayed tungsten carbide (WC) is a very successful powder applied to protect metal surfaces against wear and corrosion-erosion in industries. WC has high hardness and fracture toughness and hence it shows good wear resistance. The HVOF coatings, Plasma spray coating and PVD coatings are the techniques used to coat the tube tex rollers. There are various methods to determine the property of coatings and micro hardness measurement is a method to measure hardness and hence to measure the wear resistance. The base materials EN8 and EN19 were coated with tungsten carbide using Plasma Spray coating method. On the coated specimen, hardness tests were conducted. The hardness values are increased due to WC coatings and hardness is better than the HVOF coated samples and much better than the uncoated samples. Novelty of this work is to increase the hardness of the textile rollers to withstand the wear and tear. Hence these coatings will be more useful for increasing the wear resistance and recommended for Textile mill components.

Fuel Clad Chemical Interaction (FCCI) is one of the life limiting issues in the MOX fuel pins of fast breeder reactors. Clad wastage due to FCCI coupled with stress arising from fission gas pressure and Fuel Clad Mechanical Interaction (FCMI) due to fuel swelling can lead to fuel pin failure. Non-destructive evaluation (NDE) techniques such as Gamma Scanning, Eddy current testing and Neutron Radiography have been successfully used on MOX fuel pins of a test sub-assembly irradiated in Fast Breeder Test Reactor (FBTR) to a burn-up of 112 GW d/t to detect signatures of FCCI. The results obtained by the various NDE techniques have been correlated and verified through metallographic examination on fuel pin cross-sections. The measured clad wastage of 85 μm agrees well with a model developed for MOX fuel with high Pu content. The results of examinations have enabled validation of the model and given confidence to the designer that PFBR MOX fuel can safely attain the target burn-up of 100 GW d/t.

Fast reactor cores employ a large number of sub-assemblies for neutron and gamma shielding constituting more than 60% of the core volume. Use of effective and economical shielding materials can significantly improve the safety and cost competitiveness of fast reactors. Ferroboron has been identified as an efficient neutron shielding material for deployment in future commercial breeder reactors in India that can lead to significant cost savings. After successful shielding experiments and out-of-pile compatibility tests, a SS 304L clad irradiation capsule containing ferroboron powder has been subjected to an accelerated irradiation test in Fast Breeder Test Reactor (FBTR) to a peak neutron fluence of 8.18E21 n/cm2 for evaluating its in-reactor performance. Results of Post Irradiation Examinations carried out on the irradiation capsule to assess the various performance parameters such as slumping of ferroboron stack, helium release and chemical interaction of SS 304L with ferroboron are reported here. The examinations have indicated that extent of slumping is less than 1% and pressure build up due to helium release is 0.17 MPa (at room temperature), which are well within the permissible limits. A maximum clad wastage of 20% of wall thickness has been observed due to chemical interaction with lithium produced from (n,α) reaction. The irradiation performance assessment of ferroboron indicates its suitability for in-core shielding application in fast reactors.

Cold worked austenitic stainless steel type AISI 316 is used as the material for fuel cladding and wrapper of the Fast Breeder Test Reactor (FBTR), India. The evaluation of mechanical properties of these core structurals is very essential to assess its integrity and ensure safe and productive operation of FBTR to very high burn-ups. The changes in the mechanical properties of these core structurals are associated with microstructural changes caused by high fluence neutron irradiation and temperatures of 673–823 K. Remote tensile testing has been used for evaluating the tensile properties of irradiated clad tubes and shear punch test using small disk specimens for evaluating the properties of irradiated hexagonal wrapper. This paper will highlight the methods employed for evaluating the mechanical properties of the irradiated cladding and wrapper and discuss the trends in properties as a function of dpa (displacement per atom) and irradiation temperature.