Engineering Science 1021A/B Lecture Notes - Lecture 26: Aluminosilicate, Feldspar
17 May 2018
School
Department
Professor
Clay is an aluminosilicate (i.e. Al2O3and SiO2) with a variety of impurities
(usually various other oxides)
•
Common clay products include:
Building bricks, tiles, sewer pipes, pottery, porcelain, china
○
•
Clay products are made from various proportions of:
Clay and a flux material
Feldspar
Clay with potassium, sodium, calcium ions (modifiers)
□
§
Sheet silicate structure
§
○
Filler materials (typically crushed quartz)
Crystalline
§
○
•
Fabricating Clay Products
Clay is mixed with water to form a plastic body and formed to the desired shape
1.
Wet body is then dried and fried
Drying removes water from the clay at a controlled rate
○
Frying vitrifies the clay (turns it into a glass)
○
Degree of vitrification depends on firing temperature
○
2.
Microstructure of Clay Products
Crystalline particles surrounded by a glassy matrix with some pores•
•
Clay
