Raphael Lima de Paiva

Universidade Federal do Piauí | UFPI · Mechanical Engineering

Nickel-based Inconel 718 stands out from other materials due to its peculiar combination of properties such as high mechanical strength, high hardness, high chemical inertia and low thermal expansion, as well as its ability to operate at high temperatures and in cryogenic conditions. These properties make this material suitable for aeronautic appli...

The use of coolant during grinding process is indispensable to avoid and/or attenuate any possible thermal damages on the workpiece. However, the conventional cooling-lubrication technique (flood system) has some drawbacks, especially regarding the fact that most of the coolants are harmful to environment and human healthy, besides higher costs, ma...

The correct selection of cutting parameters is crucial to provide tribological conditions that contribute to meet the required workpiece surface topography characteristics, especially considering abrasive processes such as grinding. The present work sought to evaluate the influence of several cutting parameters on surface topography of Inconel 718...

Nickel-based superalloys present excellent thermo-mechanical properties that can be maintained at high temperatures, making them suitable for application in aerospace and nuclear industries. Such components require a combination of superior surface finish and tight dimensional tolerances, thus grinding is the first option. However, these properties...

The use of cutting fluid is crucial in the grinding process due to the elevated heat generated during the process which typically flows to the workpiece and can adversely affect its integrity. Considering the conventional technique for cutting fluid application in grinding (flood), its efficiency is related to certain factors such as the type of fl...

O processo de retificação tem como característica uma elevada energia específica de corte, o que leva ao desenvolvimento de temperaturas que podem acarretar danos de origem térmica à peça, prejudicando, portanto, sua integridade superficial. Assim, a temperatura da zona de contato durante o processo de retificação é um parâmetro importante a ser co...

The elevated heat generation in grinding can develop high temperatures at the contact zone, which can adversely affect the surface integrity of the workpiece, especially when grinding hardened steels with conventional abrasives. Thus, the correct selection of cooling-lubrication condition is essential to avoid or attenuate any possible negative eff...

Nickel-based superalloy Inconel 718 is widely used for aeronautical applications, such as blades and discs of aircraft engines, and therefore is generally submitted to a grinding process in order to meet the required surface finish and dimensional accuracy. However, the mechanical and thermal properties of Inconel 718 make it a material with low ma...

One of the peculiarities associated with the grinding process is the large amount of heat generation. Therefore, the cooling−lubrication technique plays an important role and must be conducted efficient. Even though the conventional cooling−lubrication technique generally outperforms all other techniques, its use is harmful to both the environment...

The application of cutting fluid in grinding operations is crucial to control temperature levels and prevent thermal damage to the workpiece. Water-based (emulsions and solutions) coolants are used in grinding operations owing to their excellent cooling capability and relatively lower cost compared to neat oils. However, the cutting fluid efficienc...

Despite of technological advances in developments of cutting tools such as carbide inserts, ceramic materials and others in the last three decades, some of cutting tools still needs to have their cutting geometry restored due to wear through the sharpening operation with abrasive wheels. Sharpening aims to provide shape either to new cutting tools...

Despite of technological advances in developments of cutting tools such as carbide inserts, ceramic materials and others in the last three decades, some of cutting tools still needs to have their cutting geometry restored due to wear through the sharpening operation with abrasive wheels. Sharpening aims to provide shape either to new cutting tools...

The use of cutting fluid in grinding operations is indispensable to avoid thermal damages on the workpiece. Usually a Large amount of cutting fluid is employed, but industries are currently searching for more eco-friendly alternatives and more energy-efficient process. A viable solution can be achieved by optimising the geometry of nozzles. This wo...

INTRODUCTION The removal mechanism during an abrasive process mainly depends on the physical properties and the tribological interactions between the workpiece and abrasive wheel. In hard-brittle materials the interaction with the abrasive grains results in crack formation where the volume of a chip removed can be several times higher than the volu...