Smart Ceramic Materials Research Articles

Analytical Modeling and Experimental Study of Machining of Smart Materials using Submerged Abrasive Waterjet Micromachining Process

Smart materials are new generation materials which possess great properties to mend themselves with a change in environment. Manufacturing of these materials is a huge challenge, particularly at micron scale due to their superior mechanical properties such as high hardness, high compressive strength and chemical inertness. This research investigates submerged abrasive waterjet micromachining (SAWJMM) process for machining smart ceramic materials. The research also involves experimental study on micromachining of smart materials using an in-house fabricated SAWJMM setup. The study found that SAWJMM process is capable of successfully machining smart materials including shape memory alloys and piezoelectric materials at the micron scale. An analytical predictive model is developed to estimate the MRR during SAWJMM process and the model is found to be capable of accurately predicting the machining results within 10% error. [Submitted 14 January 2018; Accepted 26 May 2018]

Experimental and Modeling Study of Liquid-Assisted—Laser Beam Micromachining of Smart Ceramic Materials

Smart ceramic materials are next generation materials with the inherent intelligence to adapt to change in the external environment. These materials are destined to play an essential role in several critical engineering applications. Machining these materials using traditional machining processes is a challenge. The laser beam micromachining (LBMM) process has the potential to machine such smart materials. However, laser machining when performed in air induces high thermal stress on the surface, often leading to crack formation, recast and re-deposition of ablated material, and large heat-affected zones (HAZ). Performing laser beam machining in the presence of a liquid medium could potentially resolve these issues. This research investigates the possibility of using a Liquid Assisted—Laser Beam Micromachining (LA-LBMM) process for micromachining smart ceramic materials. Experimental studies are performed to compare the machining quality of laser beam machining process in air and in a liquid medium. The study reveals that the presence of liquid medium helps in controlling the heat-affected zone and the taper angle of the cavity drilled, thereby enhancing the machining quality. Analytical modeling is developed for the prediction of HAZ and cavity diameter both in air and underwater conditions, and the model is capable of predicting the experimental results to within 10% error.

Smart ceramic materials for homogeneous combustion in internal combustion engines: A review

The advantages of using ceramics in advanced heat engines include increased fuel efficiency due to higher engine operating temperatures, more compact designs with lower capacity cooling system. Future internal combustion engines will be characterized by near zero emission level along with low specific fuel consumption. Homogenous combustion which realized inside the engine cylinder has the potential of providing near zero emission level with better fuel economy. However, the accomplishment of homogeneous combustion depends on the air flow structure inside the combustion chamber, fuel injection conditions and turbulence as well as ignition conditions. Various methods and procedures are being adopted to establish the homogeneous combustion inside the engine cylinder. In recent days, porous ceramic materials are being introduced inside the combustion chamber to achieve the homogeneous combustion. This paper investigates the desirable structures, types, and properties of such porous ceramic materials and their positive influence on the combustion process.

Smart Ceramic Materials for Homogeneous Combustion in Internal Combustion Engines - A Review

Smart Ceramic Materials for Homogeneous Combustion in Internal Combustion Engines - A Review

Finite element analyses of crack problems in piezoelectric structures

The widespread application of smart ceramic materials integrated in microelectronic, mechatronic and adaptive structures requires high reliability and durability of the ceramics under external and internal stresses. Therefore, fracture mechanics concepts have to be applied to crack-like defects in piezoelectric structures subjected to electrical and mechanical loads. Suitable numerical methods are suggested for computing the singular coupled electrostatic and anisotropic elastic fields at the crack tips and for determining the fracture controlling parameters like stress intensity factors and energy release rates. Three finite element techniques are presented: (i) special crack tip elements (CTE) with embedded singularity, (ii) numerical realisation of the crack closure integral, (iii) calculation of electromechanical energy balance integral. The efficiency and the performance of these techniques are verified with sample problems and compared to each other.