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The main aim of this research was to fabricate novel African teff and snake grass fibers reinforced hybrid epoxy composites with bio castor seed shell powder as filler using compression molding method as a function of varying fiber weight fraction from 5 to 25 wt%. The African teff and snake grass fibers were chemically treated with 5% NaOH to enhance fiber outer surface by removing hemicellulose, lignin, wax, and oil contents. The tensile, flexural, impact, interlaminar shear strength, and hardness of the alkaline treated hybrid composites were determined as per ASTM standards to evaluate the effect of fiber weight fraction on the developed composites. The chemical bonding between the treated fiber and NaOH agents was verified through Fourier transform infrared analysis. The adhesion between the treated fiber and matrix was analyzed by using a scanning electron microscope. The results of the investigation indicated that the mechanical properties improved with the increase in African teff fiber up to 20 wt. % and deteriorated thereafter. It was also observed that the combined influence of bio castor seed shell powder along with natural fibers over the mechanical properties was higher.

Austenitic stainless steels are the major material of construction for the fast breeder reactors in view of their adequate high temperature mechanical properties, compatibility with liquid sodium coolant, good weldability, availability of design data and above all the fairly vast and satisfactory experience in the use of these steels for high temperature service. All the Nuclear Steam Supply System (NSSS) components of FBR are thin walled structure and require manufacture to very close tolerances under nuclear clean conditions. As a result of high temperature operation and thin wall construction, the acceptance criteria are stringent as compared to ASME Section III. The material of construction is Austenitic stainless steel 316 LN and 304 LN with controlled Chemistry and calls for additional tests and requirements as compared to ASTM standards. Prototype Fast Breeder Reactor (PFBR) is sodium cooled, pool type, 500 MWe reactor which is at advanced stage of construction at Kalpakkam, Tamilnadu, India. In PFBR, the normal heat transport is mainly through two secondary loops and in their absence; the decay heat removal is through four passive and independent safety grade decay heat removal loops (SGDHR). The secondary sodium circuit and the SGHDR circuit consist of sodium tanks for various applications such as storage, transfer, pressure mitigation and to take care of volumetric expansion. The sodium tanks are thin walled cylindrical vertical vessels with predominantly torispherical dished heads at the top and bottom. These tanks are provided with pull-out nozzles which were successfully made by cold forming. Surface thermocouples and heaters, wire type leak detectors are provided on these tanks. These tanks are insulated with bonded mineral wool and with aluminum cladding. All the butt welds in pressure parts were subjected to 100% Radiographic examination. These tanks were subjected to hydrotest, pneumatic test and helium leak test under vacuum. The principal material of construction being stainless steel for the sodium tanks shall be handled with care following best engineering practices coupled with stringent QA requirements to avoid stress corrosion cracking in the highly brackish environment. Intergranular stress corrosion cracking and hot cracking are additional factors to be addressed for the welding of stainless steel components. Pickling and passivation, Testing with chemistry controlled demineralised water are salient steps in manufacturing. Corrosion protection and preservation during fabrication, erection and post erection is a mandatory stipulation in the QA programme. Enhanced reliability of welded components can be achieved mainly through quality control and quality assurance procedures in addition to design and metallurgy. The diverse and redundant inspections in terms of both operator and technique are required for components where zero failure is desired & claimed. This paper highlights the step by step quality management methodologies adopted during the manufacturing of high temperature thin walled austenitic stainless steel sodium tanks of PFBR.

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The term "Quality management" has a specific meaning within many business sectors. Quality has metamorphosed from the synonyms of "Customer satisfaction" to "Customer delight", thriving for excellence in every sphere of business with continuous improvements. In today's business scenario, more often quality is perceived as "Fitness for purpose "focusing on the customer. But there is horizon beyond this as, "quality" is always intertwined with "safety and reliability" if the nature of the business is perilous. The prime focus for any nuclear industry is about the safety and reliability which can be accomplished only through the inherent quality. The quality embarks right from the construction phase of the nuclear power plant till the decommissioning and the four main components i.e. quality planning, quality control, quality assurance and quality improvement trek alongside. The high temperature low pressure system of fast breeder reactors using sodium as the coolant demands very high reliability and high degree of quality during each and every stage of construction of all the individual components for trouble free operation of the reactor for the committed years. The "Quality Assurance (QA)" plan of Prototype Fast Breeder Reactor is unique. The reactor being first of its kind in India, quality assurance starts right from the raw material procurement and extends through all the stages of plant till commissioning. The principal material of construction being stainless steel for the reactor components shall be handled with care following best engineering practices coupled with stringent QA requirements to avoid stress corrosion cracking in the highly brackish environment. Integranular stress corrosion cracking and hot cracking are additional factors to be addressed for the welding of stainless steel components. The low alloy ferritic steel like 9Cr-1Mo (mod) has been extensively deployed and the fabrication requires structured inspection, testing and QA plan. Corrosion protection and preservation during fabrication, erection and post erection is mandatory be it reinforcement bar or a reactor vessel.