It is a part of the Tata Group.Formerly known as Tata Iron and Steel Company Limited (TISCO), Tata Steel is among the top steel producing companies in the world with an annual crude steel capacity of 34 million tonnes. It is one of the world's most geographically diversified steel producers, with operations and commercial presence across the world. The group (excluding SEA operations) recorded a consolidated turnover of US$19.7 billion in the financial year ending 31 March 2020. It is the second largest steel company in India (measured by domestic production) with an annual capacity of 13 million tonnes after Steel Authority of India Ltd. (SAIL). TATA Steel, along with SAIL and Jindal Steel and Power, are the only 3 Indian steel companies that have captive iron-ore mines, which gives the three companies price advantages.The Key Managerial Personnel (KMP) at Tata Steel Limited India are Koushik Chatterjee as CFO(KMP) and Parvatheesam Kanchinadham as COMPANY SECRETARY. Koushik Chatterjee, Mallika Srinivasan, Chandrasekaran Natarajan and 7 other members are presently associated as directors.Tata Steel operates in 26 countries with key operations in India, Netherlands and the United Kingdom, and employs around 80,500 people. Its largest plant (10 MTPA capacity) is located in Jamshedpur, Jharkhand. In 2007, Tata Steel acquired the UK-based steel maker Corus. It was ranked 486th in the 2014 Fortune Global 500 ranking of the world's biggest corporations. It was the seventh most valuable Indian brand of 2013 according to Brand Finance.In July 2019 Tata Steel Kalinganagar (TSK) was included in the list of the World Economic Forum's (WEF's) Global Lighthouse Network.Tata Steel has been recognised amongst India's Best Workplaces in Manufacturing 2022 by Great Place to Work. This recognition has been received for the fifth time, highlights the company's sustained focus on fostering a culture of high-trust, integrity, growth, and care for the employees. Tata Steel has also been inclusive towards its LGBTQ employees and also provides health insurance benefits for partners of its LGBTQ employees under the new HR policy.In November 2021, Tata Steel became the most profitable company in the Tata Group, overtaking Tata Consultancy Services.
Polyimide (PI) is widely recognized for its excellent thermal stability, mechanical strength, and film-forming capability, making it an attractive material for protective coatings. However, conventional strategies involving nanofiller incorporation often suffer from filler agglomeration and poor interfacial compatibility, which can deteriorate coating integrity and long-term corrosion resistance. In the present work, a polyimide-polydimethylsiloxane (PI-PDMS) hybrid coating was developed by chemically integrating flexible siloxane segments into the polyimide backbone to simultaneously enhance corrosion protection, tribological performance, and surface hydrophobicity without particulate fillers. FTIR and Raman analyses confirmed complete imidization and successful incorporation of PDMS, as evidenced by the appearance of characteristic imide and Si-O-Si vibrations. The incorporation of 3 wt% PDMS significantly enhanced the barrier performance, yielding an impedance modulus of 2.56 × 107 Ω·cm2 in 3.5 wt% NaCl solution. The optimized PI-SI-3 coating also exhibited a water contact angle of 126.2°, demonstrating pronounced surface hydrophobicity. Dynamic mechanical analysis revealed that pure PI possessed the highest storage modulus (1770 MPa), whereas PI-SI-3 exhibited the highest damping capability with a tan δ of 1.84 at 174 °C, indicating an improved balance between stiffness and energy dissipation. In addition, PI-SI-3 showed a low electrical conductivity of 4.60 × 10–6 S·cm−1 and a dielectric constant of 2.28 at 2 MHz, highlighting its excellent insulating characteristics. The incorporation of PDMS also markedly enhanced the tribological performance by reducing the coefficient of friction from 0.80 for pure PI to 0.13 for PI-SI-3, accompanied by a significant reduction in wear rate. The enhanced protective performance is attributed to the synergistic effect of the rigid polyimide framework and the flexible, low-surface-energy PDMS segments, which collectively improve coating compactness, hydrophobicity, and interfacial lubrication. These findings demonstrate that PI-PDMS hybrid coatings offer an effective strategy for developing multifunctional organic coatings for long-term protection of steel substrates in aggressive environments.
Recent breakthroughs in medium-manganese steels have redefined paradigms for metastable austenite engineering in advanced high-strength steels. The present contribution elucidates the thermodynamic and kinetic principles governing microstructure evolution during intercritical annealing and subsequent hot/warm forming. Particular attention is given to steel processing, highlighting how double annealing and hot/warm stamping can tailor mechanical properties (e.g., achieving 1000 MPa of tensile strength with 35
The release of phosphate into water bodies promotes eutrophication and disrupts water treatment processes, highlighting the need for efficient phosphate removal technologies in water systems. This study examines the performance of FerrIX A33E, an iron nanoparticle-impregnated strong-base anion exchange resin, for phosphate removal in water using batch and fixed-bed column ion exchange experiments. The Freundlich equation fitted the isotherm data well (R2 > 0.999), with the coefficients Kf = 3.621 (mg P)0.7805L0.2195g− 1 and 1/n = 0.2195. Batch kinetic data were analysed using first-order reversible, Elovich, and particle diffusion models at varying mixing speeds, with the first-order reversible and Elovich models providing the best description of the experimental results. A dual mechanism for phosphate removal with FerrIX A33E involving ion exchange and sorption/complexation with iron oxides was suggested. To understand the effects of key operational parameters on column breakthrough curves (bed height, inlet concentration, and flowrate), conventional models including Bohart-Adams, Thomas and Clark models in conjunction with newly developed models B-A n order and fractal models were used to describe the experimental data. The B-A n order and fractal models were found most suitable due to the asymmetric nature of the breakthrough curves. The resin was successfully regenerated using 5
SAE 9254 chromium–silicon alloy steel is widely used for automotive coil springs due to its high strength and excellent fatigue resistance. However, premature fatigue failures observed during validation testing have raised concerns regarding manufacturing robustness. This study investigates the root cause of fatigue failure in SAE 9254 coil springs supplied to an automotive spring manufacturer. Two failed springs were examined using mechanical testing, fractography, and advanced microstructural and compositional analyses. Fractographic examination revealed characteristic thumbnail-type fatigue features with well-defined beach marks, indicating crack initiation from surface defects. Scanning electron microscopy identified distinct crack initiation, propagation, and final fracture regions, while energy-dispersive spectroscopy detected oxygen, silicon, and traces of chromium and manganese at the crack origin, suggesting surface oxidation and scale formation. Metallographic analysis showed a tempered martensitic microstructure in the core; however, a decarburized surface layer and surface irregularities acted as stress concentrators, reducing surface hardness and fatigue resistance. The average hardness was approximately 576.17 HV, and bulk chemical composition complied with SAE 9254 specifications, eliminating material chemistry as the cause of failure. The results indicate that the premature fatigue failure was primarily process-induced, associated with surface defects, oxidation, and decarburization during wire preparation and heat treatment. Improved surface quality control, optimized heat treatment parameters, and enhanced coating practices are recommended to extend the service life and improve the fatigue performance.
DRI in EAFs will reduce the availability of blast-furnace slag, necessitating alternative SCMs. Five DRI-EAF slags (four engineered, and one industrial) were investigated, spanning CaO/SiO2 approximate to 1.3 or 2.0, FeOx approximate to 25 or 40 wt%, and cooling (air-cooled vs water-granulated). At 25 wt% clinker replacement, hydration and performance were quantified by isothermal and R3 calorimetry, UPV, autogenous shrinkage, XRD/TGA, compressive strength, and leaching. Cooling history, through the control of the amorphous fraction, governed reactivity: water-granulated slags exhibited higher cumulative heat, accelerated set, and superior strength activity indices compared to aircooled analogues. Basicity and FeOx exerted secondary effects: higher basicity accelerated hydration and reduced autogenous shrinkage, whereas elevated FeOx retarded reaction. All binders formed C-S-H, ettringite, and portlandite; hydrotalcite-like LDHs were detected only for the low-basicity, water-granulated slag. All mortars complied with Dutch leaching limits and met SCM strength benchmarks, evidencing the viability of engineered DRI-EAF slags as low-CO2 cementitious binders.
