An Investigation into the Development of Prospective Indian Austenitic Stainless Steels

The development of substitute stainless steels in which all or the bulk of nickel in the standard austenitic stainless grades is replaced by manganese became it live issue in many steel -producing countries during world War 11 due to restricted or nonavailability of nickel . The research and development work carried out during the war period yielded a series of commercially useful alloy steels, which are enumerated. The paper goes on to refer to an investigation in progress in the National Metallurgical Laboratory into the development of substitute austenitic stainless steels based on the use of manganese, nitrogen , copper, chromium and rare earth additions.The results of experi-mental heats made are presented in terms of working prop-erties , metallographic studies, corrosion resistance under different media, interoranular brittleness and physical tests, etc. Tentative views are expressed on the merits of these austenitic stainless compositions under Indian conditions , which will be reviewed after further work which is being pursued in the National 'Metall-urgical Laboratory along lines stated

Some problems of iron and steelmaking in the Hindustan Steel plants

The Credit for pioneering the growth of a fully integrated and well-planned iron and steel industry in India undoub-tedly goes to the house of Tata, which started from a humble beginning and grew to a mighty iron and steel complex.The Government of India has further, under the tempo of five year plans, fully realized the importance of well-knit heavy iron and steel bases to feed the chain reaction.growth of secondary and processing engineering industries, in turn forming the backbone of consumer indus-tries catering to the requirements of diverse products essential in times both of war and peace. Even though the iron and steel industry is highly capital intensive, it cannot be left to the vagaries of international trade agreements and barter arrangements to meet iron and steel requirements for almost unlimited applications in industry

Manufacture in India of Ferro Alloys used in Alloy Steel Industry

The paper starts with an outline of established methods of manufacture of different ferro-alloys required for making alloy steels with a comparison of their merits as judged by the products made. The ferro-alloys discussed include those based on manganese, chromium, silicon, tungsten, vanadium and phosphorus and of different qual-ities and grades. The position of the production of the individual ferro-alloys in India is discussed and the great importance emphasized of expanding production of those required in relation to the expansion of the Indian iron and steel industry. A programme of ferro- alloy production is outlined, with discussion of availability of raw materials, manufacturing capacity and economic factors

Theoretical considerations for substitutions in alloy steels

THE development of materials possessing certain specific properties was followed on empirical basis in the past. This was specially true in alloy steels, where there are plenty of complications and variables, each effecting the properties sought in its own way. As the theoretical background of this behaviour was least understood, development of materials in the nine-teenth and early twentieth century was based on very laborious approach which was time consuming on the first hand and costly on the other hand. Quite lately attempts have been made to rationalise the metal science on more scientific basis, and although the dream of the designing alloys by slide rule, posse-ssing the required properties, is still far from being achieved, the production costs and wastage in time can be avoided to a considerable extent by it proper application of the factors which have been understood lately. It is the object of this paper to describe these factors in detail so that the attempts in future will he based on more realistic and scientific lines than hitherto followed

Economic utilization, recovery and substitution of some strategic non-ferrous metals

With the increased tempo of industrial expansion and the ever rising consumption of common nonferrous metals like copper, lead, zinc, tin, deficient in India, their conservation, substitution, reclamation from waste pro-ducts and substandard raw materials are of paramount importance for India, not only to tide over the present crisis but also in the larger interest of economic growth and self-sufficiency. Self-sufficiency can be attained by developing processes for the utilization of low grade and other complex ores, recovery of metals from waste products like slags, ashes, drosses and above all by the conservation of non-ferrous metals not avail-able in the country by their judicious use and subst-itution

The Effect of Misch Metal Additions on the Structure and Workability of Al-Mg (7-100/.) Alloys

ON the alloying elements used in aluminium alloys, copper was one of' the earliest employed commercially and for many years it has been the principal one. Aluminium-copper alloys to which manganese, magnesium or silicon has been added, belong to the important group generally known as "Duralumin". The binary alloys of aluminium with magnesium attra- cted the interest of investigators as early as 1900. There have been numerous attempts to utilise for general purposes alloys containing as Much as 10% magnesium ; alloys containing up to 30% magnesium have been used for special purposes

Hot Dip Aluminising of Steel Wire- Laboratory Scale Investigations and Pilot Plant Studies

Protective quality of aluminium due to its adherent surface oxide film is well known. In hot-dip aluminising the use is made of this protective nature of aluminium by coating the steel base by dipping it in molten aluminium bath there-by getting an outer aluminium layer & an iron-aluminium layer at the interface. The interfacial alloy layer though possessing good atmospheric corrosion and resistance to oxidation at high temperature is brittle in nature and such must be kept to a minimum of thickness where the end use of aluminised product is for deep drawing, forming etc. Hot-dip aluminium coating on steel base comprising the outer aluminium layer and an alloy layer in the interface should possess both atmospheric & high temperature corrosion resistance

Carotenoid biosynthesis genes in rice: structural analysis, genome-wide expression profiling and phylogenetic analysis

Carotenoids, important lipid-soluble antioxidants in photosynthetic tissues, are known to be completely absent in rice endosperm. Many studies, involving transgenic manipulations of carotenoid biosynthesis genes, have been performed to get carotenoid-enriched rice grain. Study of genes involved in their biosynthesis can provide further information regarding the abundance/absence of carotenoids in different tissues. We have identified 16 and 34 carotenoid biosynthesis genes in rice and Populus genomes, respectively. A detailed analysis of the domain structure of carotenoid biosynthesis enzymes in rice, Populus and Arabidopsis has shown that highly conserved catalytic domains, along with other domains, are present in these proteins. Phylogenetic analysis of rice genes with Arabidopsis and other characterized carotenoid biosynthesis genes has revealed that homologous genes exist in these plants, and the duplicated gene copies probably adopt new functions. Expression of rice and Populus genes has been analyzed by full-length cDNA- and EST-based expression profiling. In rice, this analysis was complemented by real-time PCR, microarray and signature-based expression profiling, which reveal that carotenoid biosynthesis genes are highly expressed in light-grown tissues, have differential expression pattern during vegetative/reproductive development and are responsive to stress

An improved PV system with auto-protection to inject active power into the power grid of marine ships

1132-1142Photovoltaic (PV) system is turning into an ideal secondary power source for marine ships because of the ability to trap nature’s green energy. In this paper, a ship’s power grid connected PV system is proposed. The proposed system will help to inject the active power into the ship’s electric power grid together with a protection scheme, which will prevent the PV system and ship’s power grid from different faulty conditions. The proposed system has facility to track the maximum power point (MPP) of PV array by means of hybrid MPPT method and flyback DC-DC converter. Space vector pulse width modulation (SVPWM) technique controlled 3-phase full-bridge VSI is used to convert DC bus voltage into useful 3-phase AC output in order to feed the local load and transmit excess AC power into the ship’s bus. Furthermore, an isolation transformer is used to provide galvanic isolation amid PV system and ship’s power grid