Experimental investigtion on machining of microalloyed steel using k20 carbide inserts

Abstract

Steels of any kind such as low, medium and high carbon play a vital role in manufacturing most of the engineering/machine components. The engineering components require some essential mechanical properties and microstructures to meet the expected performances in the application. In order to attain the desired mechanical properties and the microstructures for specified application, these steels have to undergo follow up manufacturing processes like heat treatment processes following to the foundry process. This leads to the increase in the cost of the product and this also raises the energy cost to the manufacturing industries. Hence, industries face a real challenge to overcome higher expenses and to comply with energy conservation objective in production process. The development of material technology influenced the addition of micro alloying elements such as Niobium, Vanadium, boron and Titanium along with other alloying elements in the steels. The additions of micro alloying elements in the steel do not exceed by 0.15% either individually or cumulatively. This addition of micro alloying elements is normally done in the melt itself, which results in solid solution strengthening(Precipitation strengthening)mechanisms and thereby the steel has ferrite-pearlite microstructures without heat treatment. Whereas the carbon steels have to be sent to heat treatment to attain high strength the banite structure. Vanadium based micro alloyed steel is better among the other elements due to its better chemical/metallurgical reactions. This type of steel is known as Micro Alloyed Steel(MAS). These MAS show higher strength of around 800MPa than the conventional and heat treated steel. In the earlier period of 19th century this steel was identified as structural steel. Later the MASs were widely implemented in automotive parts where high strength and toughness are required. Most of the vanadium based micro alloyed steels are widely deployed in producing auto components such as crankshaft, connecting rod, wheel hub etc. Generally, the MAS is produced in the form of hot rolled bars, forged parts and flats. The micro alloyed steel replaced the carbon steels and it acts as a bridge for cost and performances between the low alloy and carbon steels. The major factors of the micro alloyed steel such as good strength to weight ratio, greater weight reduction, superior formability and elimination of heat treatments have increased the utilization of this steel by the manufacturing industrie newline