Lesson 4 - Materials Application in Brewing
In this lesson we will discuss materials and their application in greater detail. This will include understanding their properties, advantages and disadvantages, and their main applications in the brewery. We will place emphasis on the materials most common in the brewing industry.
Ferrous Metals
Ferrous metals have played a major role in the modern world. Just like humanity evolved from the Stone Age to the Bronze Age to the Iron Age, the brewing industry has also evolved from using clay pots and ceramic vessels, to copper vessels and onto stainless steel vessels.
The term ferrous metal is used for all metal alloys having iron as the major constituent. Pure iron is a relatively soft material and hardly used.
An alloy is any metal which is composed of two or more metallic materials. Alloys of iron with carbon content less than 2.14% by weight are classified as steels. Steels can be further sub-divided into several categories. The term ‘alloy steel’ is used where other elements are included. Typical alloying elements include manganese, aluminium, copper, nickel, chromium or cobalt. Stainless steels have high percentages of chromium and nickel, which contribute to high resistance to corrosion, in their chemical composition and are one form of alloy steels.
The earliest piece of iron found dates from 5000 bc, in the form of beads on a bracelet. This was long before iron ore smelting was developed and the source of this iron was found to be a meteorite.
Ferrous metals can be further broken down into various categories, which we will now look at in more detail. Let’s start with stainless steel.