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In recent years, asbestos and copper free brake pads have attracted researchers due to its adverse environmental risks which requires manufacturers to seek a suitable replacement. It is essential to identify new combination of synthetic and natural fibers for the potential automotive brake pads. Experiments were planned to produce various frictional composites by using additives like carbon fiber and basalt fiber with standard additional ingredients like binders, fillers, abrasives and lubricants through hot pressing technique. Here binder act as epoxy resin is mixed with these frictional composites and graphite act as lubricant, vermiculite act as filler and alumina act as abrasives. The prepared form of polymer composite brake pad materials was tested as per ASTM and industrial standard practices like hardness, wear and friction followed by worn surface roughness were measured.

Among all metal matrix composites, A356 is the most applicable matrix due to its low density and exhibits nominal strength with soft nature. This proposed study is concerned with the examination of mechanical and tribological behavior of virgin A356 alloy and A356 reinforced with 10wt.% power plant waste flyash particles composites were processed by liquid metallurgy stir cum squeeze casting technique. The fabricated composites expose enhanced higher hardness when compared to the virgin A356 alloy due to the presence of flyash particles in the matrix. The wear and friction behavior of casted samples were evaluated with a pin on disk tribometer apparatus under dry and wet sliding environment at the presence of lubricant (SAE 80W-90) by varying sliding load of 10N-40N and sliding velocity of 1-3 m/s respectively. Wear rate increase with the increasing load and sliding velocity.

Friction stir processing (FSP) is a typical process for refinement changes of microstructure, enhance material's mechanical properties, and fabricating surface layer composites. The cast A356 surface composites were fabricated via Friction Stir Processing (FSP) and the enhancement of it’s metallurgical and mechanical properties are studied and conveyed in this research study. The three combinations of test samples of FSP'ed cast A356 alloy, FSP'ed cast A356 FSP with tungsten nanoparticle addition (5 and 10 vol%) were considered to fabrication under fixed parametric conditions like tool rotational speed of 1000 rpm, a load acting 9 kN,./ tool travel speed of 20 mm min−1 through four number of tool travel passes respectively. Obtained FSP'ed samples were exposed to microstructural, tensile strength tests and fracture surface morphology analysis were carried out to record the responses.

In this appraisal, The Friction Stir Processing (FSP) was utilized to incorporate 5vol% and 10vol% of Tungsten nanoparticles for the modification of the as-cast A356 alloy properties. Keeping an eye on the stipulation to improve the wear and friction behavior of the cast A356 alloy stir zone surface, the tribometer test was done under dry sliding conditions in a pin on disc instrument on different parameters such as load applied (10-40N) and sliding velocity 1and 3m/s respectively. As a result, confirmed through scanning electron microscope image fine and equiaxed grains in the stir zone surface followed by agglomeration free uniform distribution of tungsten nano particles in the matrix as it constitutes of higher value of microhardness.

Productivity plays a vital role in manufacturing processes as well as in service. Sheet metal bending process is a type of forming process that has been used by the wide range in industries. There are several tangible and intangible factors affecting the production rate during the bending process. Spring back is one of the severe factors which affects the production rate, especially in stainless steel material. The spring back is mostly affected by material properties, sheet thickness, bending radius, die sizes and component geometry. In this paper, the spring back is studied by the effect of various parameters such as rectangle/oblong slots with varying pitch distance and without slots and bending time in the stainless-steel material 304 grade in V-air bending machine. The experimental data are evaluated by means of the Response Surface Method (RSM). Finally, it was observed that explored results have the betterment of the production rate with connection to spring back.

AA2014 Aluminum alloys are most widely used for automobile and aerospace structures where specific strength is important. Hot cracking is a major problem while welding these alloys. In the present investigation, the metallurgical studies, viz, hot cracking sensitivity, microstructure and the mechanical properties, viz, hardness and tensile strength of the 4 mm thickness AA2014 aluminum alloy were studied using two different methods. The first method involves TIG (Tungsten Inert Gas) welding with continuous current process and the second method involves TIG welding with pulsed current process. In both the process commercial argon pure gas was used as a shielding gas. The results showed that hot cracking sensitivity was decreased when the specimen was welded using pulsed current process compared to continuous current process.

Incorporating of organic fibers originated from plants in polymer composite have gained significant attention over a period of time as they provide eco-friendly lighter composites. The increasing demand by automotive sectors for wear and frictional areas where the conservation of energy is concerned is expected with addition of nano -solid lubricants. Our aim is to fabricate organic frictional composites of basalt fiber reinforced polymer composites along with three possible combination of nano - solid lubricants like (1) graphite (2) graphene (3) molybdenum disulfide through hot press technique. The outcome of the tribological tests (by varying load and sliding velocity) indicates that these three-organic fiber-based polymer composites have been effectively modified by nano-solid lubricants leading to significant enhancement. In which molybdenum disulfide- based brake pad material is an attractive material to replace the practical problems in automotive sector was the key finding.

Solution route precipitation technique was opted to synthesize the nanostructured copper tungstate by the incorporation of cupric ion solution to the aqueous sodium tungstate reagent. The size and surface of the synthesized nanostructured material is highly influenced by the concentration of cuprous ion as well as the tungstate solution. The structural pattern and chemical composition of CuWO4 nanoparticles were analysed by powder XRD and FESEM with EDX spectrum. The powder XRD and EDX pattern confirmed the elemental composition of the synthesized samples. FESEM images indicated that the particle was present in random size distribution. At 298 K, water vapour pressure thermostat was achieved in the range from 5% to 98% as a relative humidity (RH). By providing the DC conductance measurement as a relative humidity, the humidity sensing nature of the material was investigated and the sensitivity factor (Sf) value of the prepared CuWO4 was calculated at 298K (Sf=9640±100).

Pure aluminium alloy (AA) components are not extending their cyclic life due to soft nature of the surfaces for most of the automotive structural parts, exposed to various loading and stress exposed areas through various surface property enhancement techniques. Among all the technique friction stir processing (FSP) followed by shot peening (SP) technique is the most viable and cost-effective process for enhancement of component performance and SP removing residual stresses on the samples thereby improving surface strength. The main objective of the proposed work was cast A356 alloy reinforced with nano form of 6wt% silicon carbide (SiC) harder particles and 3wt% self-lubricant graphene (Gr) was used to fabricated a surface nano hybrid composite through FSP technique. SP route was performed on the FSP-ed samples with optimal parametric conditions for obtaining improved mechanical performances.

The critical components in earlier were manufactured by mild steel but due to low corrosion resistance, stainless steel and aluminium alloy are being utilised. However a component of aluminium alloy has to be enriched by anodizing for long durability and better corrosion resistance. But peel off, pit formation, low adhesion and white rust formation are still the downfalls faced by the industries in the coated components over cyclic duration. High-Velocity Oxy-Fuel (HVOF) thermal spraying is an adaptable method that can produce high-density coating with less than 1% porosity, high resistant to chemical environment providing better adhesion and increase the life of mating components. Though stainless steel and anodized aluminium alloy offers far superior life span and corrosion resistance but still more expensive than mild steel.

Hybrid Composite materials meet a major demand in current industrial market through mixture of various percentages of metal compositions at different levels. One such material, which is most widely employed, is aluminum. Aluminum hybrid metal matrix composites is substituted with conventional alloys in order to meet the rigid, high-end requirements at major industries. In this work, it is reinforced with Aluminum-Tungsten Carbide-Graphite composite and fabricated using the stir casting process. Die sinking electric discharge machining (EDM) process is preferred over conventional process for the purpose of machining complex shaped materials with accuracy. The optimization of minimizing surface roughness and maximize material removal rate is essential to increase the effective and efficient usage of hybrid composites.