"THOUGHTS OF STEEL" (PROCESS OF SHAPING AND FINISHES)

 

                                                                                                                                   21st AUGUST 2020





     Hey guy! Jeyakumar again…


     Today I would like to share about my next experience of my journey in the steel architecture class.


      Today I am going to talk about shapes, prevention of corrosion and maintain the appearance of steel.


     In the beginning, we discussed “WAY TO SHAPE STEEL…!” There are two methods of way to shape steel “HOT ROLLED METHOD“ and “COLD ROLLED METHOD

     “HOT ROLLED METHOD” is rolled out of the casting area to a specific thickness.

     “COLD ROLLED METHOD” is a product of the hot rolling process.


     Then we discussed the process of shaping steel. The process is

        I.                                              Cold hardening

      II.                                                      Quenching

    III.                                                            Tempering

    IV.                                                                     Annealing

      V.                                                                               Galvanization


       Let’s see “HOW THESE ABOVE PROCESSES WORKS?”

     “COLD HARDENING” also called as “STARIN HARDENING”, “IT IS USED TO  INCREASE STRENGTH AND HARDNESS”. It’s used by hammering and compressing.


     “QUENCHING” is used to heated steel quickly cools it by water, oil, air. “IT DOES CREATE THE THIN CRYSTAL LAYER WITH STRONG AND BRITTLE”.


     “TEMPERING” is used to “INCREASE THE STRENGTH, HARDNESS, AND DUCTILITY”. Heating and controlled cooling process.


     “ANNEALING” is a heat treatment “WHICH INCREASE STEEL’S DUCTILITY AND REDUCE IT’S HARDNESS”. By heating and cooling, it is very slow to make hard steel to soft.


     “GALIVIZATION” is the application of zinc coating to prevent rusting. It is classified into two types “HOT DIPPED” and “COLD DIPPED/ELECTRO”  


     “WHAT IS HOT DIPPED GALIVIZATION?”  

                                                    Durability- prevent oxidation,

                             Immersing metal in a bath of “MOLTEN ZINC” thin layer,

                                                       Repeated- thick coating,

                                     Corrugation should be  formed before dipping

                                        Zinc layer- self-protecting matte grey color


     “WHAT IS COLD DIPPED/ELECTRO GALIVIZATION?”  Zinc the layer is electrically created, Shiny surface, and Less durable.


     “WHAT IS THE DIFFERENCE BETWEEN HOT AND COLD STEEL SECTION?” “HOT STEEL SECTION” is easy to make and cheaper than the cold steel section. It is used for the railroad, I-section. It is usually larger in size. 1700 Fahrenheit (926 degrees Celsius). “COLD STEEL SECTION” is harder to work with, tolerance, cold reduction mills- cooling, concentricity, and straightness with the surface finish.


     We have learned that plain grey color immediately reacts with oxygen, scale and rust. We can use stainless steel for visible appeal and creates aesthetical appeal but it is costlier than other steel.


     “HOW TO PREVENT CORROSION AND MAINTAIN IT'S APPEARANCE?”  

ENCLOSED WITH GYPSM LAYER
ENCLOSING STEEL IN CONCRETE
CONCEALED FROM ITS VIEW

     “REACTION WITH FIRE” Steel is noncombustible but it will lose strength and become ductile at high temperature.


     “HOW TO PREVENT?”

PAINTED
GALVANIZED
CHEMICALLY TREATED


    “HOW TO TREAT/FINISH STAINLESS STEEL?” Polished- Brushed- Textured- Patterned- Electropolishing. This process allows for decreasing the surface roughness.


     “WHAT IS ELECTROLYTIC COLOURING?” is used to get colors like gold, bronze, red, purple, and green. It does create superficial film corresponds to ranging from 0.02µm- 0.36µm thickness.


     “WHAT IS BURNISHING?” We can get the color by dipping in chemical sodium dichromate. The surface is durable and doesn’t flake in resistant heat light abrasion.


     “WHAT IS ACID ETCHING?” Surface covered with a resistant substance that is removed in a specific area. It does create a pattern.


      “HOW PAINT WORKS?” It is used for aesthetic purposes and makes the object visible. Steel can be purchased in a pre-painted sheet or coil.


     “HOW DOES PHYSICAL VAPOUR DEPOSITION?” It does help to create colors like bronze, gold, rose gold, blue, black, and burgundy. The specific treatment enhances specific mechanical properties such as hardness, friction coefficient, resistance to starches, and wear.


    “HOW DOES METALLIC COATING WORKS?” It can combine the corrosion resistance of stainless steel with the aesthetics of another metal such as copper or tin. The coating is usually applied by galvanic processes. This layer can be damaged by scratches or wear and tear but the underneath stainless steel is not affected.

     “DO YOU KNOW ABOUT WEAT

  "WEATHERING REACTION CAUSED BY ENVIRONMENT?” “MILD STEEL” and “LOW ALLOY STEELS” are highly susceptible to reaching with oxygen and causing rust with accelerated corrosion occurring in coastal and marine locations.


•COROSSION TREATMENT
•POWDER COATING
•GALVANIZATION
•APPLYING PAINT
•COPPER ALLOY

 

     “HOW STAINLESS STEEL WORK IN ATMOSPHERIC CORROSION?” It has a high resistance to atmospheric corrosion. It retains original luster. A thin oxide film. Colored with bronze, blue, gold, red, purple, green by chemical and cathodic treatment.





                                             It does end really well with good discussion. 




                                               “ Waiting for journeys next experience”

 



 Jeyakumar V S

 

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