ASTM A36 Mild/Low Carbon Steel

Topics Covered

Introduction
Chemical Composition
Physical Properties
Mechanical Properties
Machining
Welding
Heat Treatment
Applications

Introduction

ASTM A36 is the most commonly used mild and hot-rolled steel. It has excellent welding properties and is suitable for grinding, punching, tapping, drilling and machining processes. Yield strength of ASTM A36 is less than that of cold roll C1018, thus enabling ASTM A36 to bend more readily than C1018. Normally, larger diameters in ASTM A36 are not produced since C1018 hot roll rounds are used.

ASTM A36 is usually available in the following forms:

  • Rectangle bar
  • Square bar
  • Circular rod
  • Steel shapes such as channels, angles, H-beams and I-beams.

Chemical Composition

Element Content
Carbon, C 0.25 - 0.290 %
Copper, Cu 0.20 %
Iron, Fe 98.0 %
Manganese, Mn 1.03 %
Phosphorous, P  0.040 %
Silicon, Si 0.280 %
Sulfur, S  0.050 %

Physical Properties

Physical Properties Metric Imperial
Density 7.85 g/cm3 0.284 lb/in3

Mechanical Properties

Mechanical Properties Metric Imperial
Tensile Strength, Ultimate 400 - 550 MPa 58000 - 79800 psi
Tensile Strength, Yield 250 MPa 36300 psi
Elongation at Break (in 200 mm) 20.0 % 20.0 %
Elongation at Break (in 50 mm) 23.0 % 23.0 %
Modulus of Elasticity 200 GPa 29000 ksi
Bulk Modulus (typical for steel) 140 GPa 20300 ksi
Poissons Ratio 0.260 0.260
Shear Modulus 79.3 GPa 11500 ksi

Machining

The machinability rate of ASTM A36 is estimated to be 72%, and the average surface cutting feed of ASTM A36 is 120 ft/min. Machining of ASTM A36 steel is not as easy as that of AISI 1018 steel.

Welding

ASTM A36 steel is easy to weld using any type of welding methods, and the welds and joints so formed are of excellent quality.

Heat Treatment

Any standard carburizing and hardening methods of AISI 1018 steel is suitable for ASTM A36.

ASTM A36 is subjected to the following processes:

  • Normalizing at 899°C – 954°C (1650°F-1750°F)
  • Annealing at 843°C – 871°C(1550°F-1600°F)
  • Stress relieving at 677°C – 927°C(1250°F-1700°F)
  • Carburizing at 899°C – 927°C (1650°F-1700°F)
  • Hardening at 788°C – 816°C(1450°F-1500°F)

Applications

ASTM A36 steel has the following applications:

  • It is used in bolted, riveted or welded construction of bridges, buildings and oil rigs.
  • It is used in forming tanks, bins, bearing plates, fixtures, rings, templates, jigs, sprockets, cams, gears, base plates, forgings, ornamental works, stakes, brackets, automotive and agricultural equipment, frames, machinery parts.
  • It is used for various parts obtained by flame cutting such as in parking garages, walkways, boat landing ramps and trenches.

Comments

  1. LI RONGBAO LI RONGBAO People's Republic of China says:

    for the composition figure, Cu, Mn, P, S, Si, are they bottom or top ? or average ?

    thanks.

    • Alessandro Pirolini Alessandro Pirolini United Kingdom says:

      Hi Li Rongbao,

      Thank you for your question. The composition values given are typical for the addition elements found in this particular grade of steel. The percentages of the addition elements mentioned are what define this steel as the grade that it is.

      For example, carbon steel is defined as having up to 1.65wt% manganese, and so if there is a higher percentage than this, then that particular steel would be defined differently in terms of its grade.

      There will usually be a small deviation compared to the exact percentages stated for each alloying element found in a grade of steel.

      I hope this helps.

      Alessandro

      • Namit Shah Namit Shah India says:

        Which is the best material in mild steel for submerged arc welding process and also tell the flux material.

  2. Prathamesh Deshpande Prathamesh Deshpande United States says:

    why does the TS of A36 varies from 400-550 MPa? shouldn't there be one value of TS?

    • Richard Driskill Richard Driskill United States says:

      I believe it is due to working load temperature variables. If you want a single number, I think you need a specific temperature.

      • RICHMOND YARRICK RICHMOND YARRICK Ghana says:

        You are ryt Richard .. these also make it flexible for the use of any other country. in my country A36 or S275JR has never fail if only proper design is made

    • Sayantan Das Sayantan Das India says:

      It depends on the strain rate also. Higher the strain rate, lower will be the UTS.

  3. Sulson International Sulson International Islamic Republic of Pakistan says:

    Please guide us as to whether Q235B Chinese grade is same as ASTM A 36.

  4. Balsam S Balsam S U.A.E. says:

    Can we say that A 36 is carbon steel since it has less than 1.65 wt% manganese?

  5. Myo Kyaw Win Myo Kyaw Win Singapore says:

    Is A36 sour grade material?

  6. Stevanus Arie Stevanus Arie Indonesia says:

    can i have CCT diagram for A36?

  7. akhil betha akhil betha India says:

    for a double shear performed on utm..what will be the standard ultimate shear strength?

  8. Iftikhar Ahmad Iftikhar Ahmad Saudi Arabia says:

    Hi, dear professionals, good morning
    I have a question regarding billet inspection, during physical inspection, we measure length, rheomboidity, bending , twisting, corner radius, etc & so I have to know, which standard should be followed for that.
    Waiting for your valuable response

  9. pradeepta dash pradeepta dash India says:

    sir can we use this astm a36 plate for makining c-hook for lifting 30 m/t hot rolled coils

    • RICHMOND YARRICK RICHMOND YARRICK Ghana says:

      Yea you can use it but depends the thickness you will go for.

  10. zaitul akma zaitul akma Malaysia says:

    how can i get the sn curve for this material?

  11. Cheah Ck Cheah Ck Malaysia says:

    Application - crossarm for holding the lamp, material - ASTM A36 (5.0mm thickness)
    Welding process: SMAW, service life: 20 years
    In general any concern and comment, thanks

  12. antony james antony james India says:

    can  tell anyone this material name. cu 0.05,ni 0.07,fe 99.22,mn 0.6

  13. mousab almatarneh mousab almatarneh Jordan says:

    can it use for temperature up to 400 C (NaOH 98%) as flaking drum?

The opinions expressed here are the views of the writer and do not necessarily reflect the views and opinions of AZoM.com.

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