What are ceramics?

Ceramics are used for the manufacturing process. Ceramic materials may exist in glass and crystalline solids or a combination of both. They can be inorganic and non-metallic materials. Ceramic materials possess high strength, good bonds, brittle, low thermal conductivity, anti-corrosivity, and poor conductivity.

What is ceramics processing?

Ceramics processing is the method used for the production of rigid products. Ceramics can be manufactured with the help of raw materials, clay, and heat.

The ceramics processing can be shown as below:

In the above diagram, the first process is the raw materials gathering process. The raw materials are collected from various locations then sent to the production plant. Then it is followed by the clay proportioning process and then moves to the pugging process. Then they are sent to the rolling process, and then mixing takes place. Then the obtained product, like bricks, is shaped by the extrusion process.

Then with the help of pressing operation, different shapes and sizes of bricks are obtained. After that, the excess moisture content is removed by the drying process. The final process is the firing of bricks, and it is performed in kilns equipment. Then the obtained bricks are sent for quality check and inspection and then stored for later use.

Steps for making a ceramic product

The block diagram of the steps for the developing of a ceramic product can be shown as,

In the above diagram, the raw materials are fed into the crushing milling which helps to convert the coarser grains into the finer grains, and then they are mixed with the additives like binders, lubricants, wetting agents, etc. After this, they undergo forming processes like slip casting, extrusion, pressing, injection molding, etc.

In the next step, they are sent for a drying process like green machining. The obtained product goes through the firing and sintering process. Then the specimen undergoes finishing operations like machining processes, grinding lapping, etc.

Steps involved in the traditional ceramics processing

The diagram for the traditional ceramics processing can be shown as,

In the above diagram, the first step is the preparation of raw material. It is in the form of loose powder with air spaces between them. The second step is the shaping of wet clay, and it consists of clay and water. The third process is drying, and it consists of dried clay. The next step is where the firing takes place.

Ceramic Tools and Equipments

Clay

These are particles that are decomposed forms of rock. They are meshed with water to produce a malleable structure. Then this structure is fired into kiln equipment. The particles again return into the rigid stone state form.

Potter's needle tool

For the trimming of piercing clay in the ceramic, hard pointed wire is fixed at the head of the handle.

Fork

For scoring and roughing, a dinner fork-shaped tool is used. These are used to join two parts of clay with a sip.

Fettling knife

For the trim purpose, a tapered shaped knife is utilized.

Rolling pin with wooden slats

The rolling pin is helpful for the rolling of thick layered clay. The wooden slat is the tool over which the clay is placed, and the pin rolling is performed.

They can be shown as,

Loop tools

They are employed for the trimming of clay.

Modeling tools

They are utilized for the trimming, texture application, decoration on the outer surface of the clay.

Rib tools

Rib tools are employed for smoothening of the clay.

Glaze

The glaze is generally performed for decoration, protection, and safety purposes. It is a powder form of clay, fluxes, and is mixed with water. It is applied, and then a firing operation is performed.

Cutting wire

A circular metallic wire has two handles side by side. They are used for cutting the clay.

Banding wheel

It is used for the decoration or building of pottery. It is a rotational wheel that can be rotated to turn any pottery.

Glaze brush

This brush is utilized to apply a layer of glaze to the clay. For better protection of the clay, a three-layered glaze is generally applied on the surface of the clay.

Kiln

For firing of the clay, a kiln is employed. It is a type of furnace which is made up of refractory materials. They work with the help of electricity, fuel, gas, coal, wood, etc.

Advantages of ceramics

• Ceramics exhibits low thermal conductivity.
• Ceramics can sustain high temperatures.
• Ceramics possess a low melting point
• Ceramics are less dense.
• Ceramics have less friction coefficient, high corrosion resistance, high hardness, are less costly, and manufactured efficiently.

Disadvantages of ceramics

• Ceramics can be broken while impacting as they possess less impact strength.
• Ceramics have less shock resistance.
• Ceramics have less dimensional tolerances.
• Ceramics are less tensile.

Common Mistakes

• It is a misconception that ceramics have high impact strength, rather they have low impact strength.
• Sometimes students get confused that evolutionary prototyping is the same as rapid prototyping. But both are different.
• It is a misconception that ceramics are very strong and cannot be damaged easily. But it's not true.
• It is a misconception that ceramics are also preferable as cooking utensils in an open fire. But it is not suitable to use in open fires.
• It is a misconception that ceramics have good shock resistance and are good in tension. But the converse is true.

Context and Applications

The topic of ceramics processing and equipment is common in many technical as well as professional courses, graduation courses, post-graduation, Doctor of Philosophy, and others. For example:

• Bachelor of Technology in Mechanical Engineering
• Bachelor of Technology in Civil Engineering
• Bachelor of Technology in Production Engineering
• Master of Technology in Mechanical Engineering
• Master of Technology in Production Engineering
• Master of Technology in Civil Engineering
• Doctor of Philosophy in Mechanical Engineering
• Doctor of Philosophy in Civil Engineering

Related Concepts

• Ceramics
• Ceramics manufacturing
• Ceramics and glass
• Ceramics composition and properties
• Ceramic tools and equipment
• Pottery, ceramics, stoneware, and porcelain
• Traditional and advanced ceramics

Practice Problems

Q1: Which is the following is not ceramics processes?

(a) Rolling

(b) Drying

(c) Sintering

(d) Milling

Correct option: (d)

Explanation: Ceramics processing involves clay proportioning, pugging, rolling, mixing, extrusion, pressing, drying, and firing.

Q2: Which of the following are not the ceramics tools and equipment?

(a) kiln

(b) Banding wheel

(c) Chip pan

(d) Glaze brush

Correct option: (c)

Explanation: The ceramic tools and equipment contain clay, porter's needle tool, fork, flattening knife, rolling pin with wooden slats, loop tools, modeling tools, rib tools, glaze, cutting wire, banding wheel, glaze brush, and kiln.

Q3: Which of the following does not come under ceramics processing?

(a) Extrusion

(b) Spinning

(c) Pugging

(d) Drying

Correct option: (b)

Explanation: Clay proportioning, pugging, rolling, mixing, extrusion, pressing, drying, and firing are the various processes involved during ceramic processing.

Q4: Ceramics have low ______________.

(a) Melting point

(b) Hardness

(c) Coefficient of friction

(d) Brittleness

Correct option: (c)

Explanation: The ceramics have less friction coefficient, high corrosion resistance, and a high level of hardness.

Q5: Ceramics have __________ melting point and ________ density.

(a) high, low

(b) low, high

(c) high, medium

(d) low, low

Correct option: (d)

Explanation: The ceramics have a low melting point and low density. It also has low thermal conductivity to sustain high temperatures.