Fundamental Design of Steelmaking Refractories

4 Degree of Ceramic Bonding

4.1 Introduction

When a particle compact transforms into a densified body with the help of thermal energy, the process is known as sintering. Sintering expedites the formation of ceramic bond within grains and the matrix; however, the degree of such bonds are influenced by sintering characteristics that strictly depends on several parameters, including starting particle size, temperature, time, atmosphere, etc. Sintering consists of densification and grain growth. Sintering is often used to synthesize or process basic elements of materials in science and engineering. Depending upon the shaping techniques applied to the green product, the sintering conditions need to be adjusted accordingly, which may vary the sintering techniques. Various techniques and processing variables can be altered in the sintering step to achieve desired microstructure and properties. Microstructure control means managing grain size, sintered density size, and distribution of other phases, including pores.

There are two processes into which it is divided, solid-state and liquid-state sintering. There are many pros and cons to liquid phase sintering. Some of the pros are easy to control microstructure by controlling the composition and the amount of liquid phase, one of the methods that preferably has lower processing costs, and can be used for materials that need properties of grain boundary phase. Cons are mostly a reduction in the mechanical properties of the material. ...