BLOG ENTRY 2

Hello guys!

In today's class we further looked into steel as a building material, we looked into the raw materials, involved into the making of steel which are

-iron ore

-coke 

-Limestone 

The different manufacting processes of steel:

there are two different processes involved, 

1. Basic oxygen process - Oxygen is blown into a furnace containing the pig iron from a point

Pig iron is smelted iron (Smelting is the process of applying heat to the ore) - Steel

2. Electric arc furnace process - Carbon additives are used to create an electric arc that melts the metals  - Stainless steel

The byproducts which we get are Sulphur and Silicon from these processes.

Next topic further in the books was about alloys.

What is an alloy?

An Alloy is a combination of metals, which gives the base metal increased properties for its required use.

Steel can be heat treated to form alloys with to improve its quality, like

Chromium, Manganese increases corrosion resistance and hardness

Aluminium improves surface hardening, etc 

Copper, Molybdenum increases corrosion resistance and strength.

Some important terminology discussed:

Hardness 

Tensile Strength

Ductility 

Brittleness

Hardness

Elasticity

Plastic strain 

Necking 

Fracture 

Lets see what these words mean: 

During the process of compression, when the loads apply pressure on the steel bar, the steel bar bends (due to shrinkage, the ends curve due to compression experienced in the centre and tension experienced below) after a point, the steel bar shows sign of stress ( due to the pressure applied ) is called as Necking, after a point it deforms, which is known as Facture. When the pressure is uplifted, if the bar is able to return back to its original form, then it has good elasticity. But if incase, the bar is deformed, and cannot go back to its original state, then its called a plastic strain. 

Hardness and Tensile strength are terms which map out the resistance of the material till it breaks upon tension, when observing the quality of hardness in a material, tension is applied vertically, enabling a change in its cross- sectional area, while observing the quality of tensile strength, tension is applied on the sides, externally.

How can we say a material is an ideal architectural material?

It needs to be affordable, easy to work with, conductive to heat and electricity, lustrous, attractive and corroded by oxidation. 

Coming to steel, 

Its easy to assemble, disassemble and replace anywhere. 

It has a long life span.

Easy of handling steel in the pre-fabrication process.

It can be strengthened by connecting additional sections and plates

Very easy to inspect it, because it doesnt have a covering, its easy to check for maintence.

Certain cons are,

It is very expensive 

Its hard to get skilled labourers to handle the scale of construction with steel 

and it corrodes easily. 

The class ends with a small discussion as to whether steel is sustainable or not, certain important insights were shared. 

Is steel sustainable or not?

It can be and it also isnt in certain other ways.

Steel is a long-standing material, with probably a one-time investment, and no further expenses in regards to maintening it. Its manufacturing process is not toxic, it doesnt harm the environment in any way, and its wastage while manufacturing can also be reused. Its an endlessly recyclable material in nature. But it cannot handle the changing weather conditions, and corrodes easily compromising the quality of the material.

The atmosphere of this class is starting to really grow me, giving me the sense of being part of a community. Very easy to make your voice heard and be comfortable with the rest of peers. Looking forward to more fun intereactions!

Signing off,

Tejashri Kumaresan