Heat treatment and properties of 08 # steel

Chemical elements of 08 # steel:
C content: 0.05-0.12;
Si content: 0.17-0.37;
Mn content: 0.35-0.65;
S content ≤ 0.035;
P content ≤ 0.035;
Cr content ≤ 0.10;
Ni content ≤ 0.25;
Cu content ≤ 0.25

08 # steel material name:
High quality carbon structural steel, grade: 08, standard: GB/T 699
Characteristics and scope of application of 08 # steel:
Most of the 08 # steel is rolled into high-precision thin plates or cold rolled steel strips for manufacturing deep stamping or deep drawing covering parts and welding components that are easy to process and form and have low strength. It has high plasticity, toughness, welding performance, good pressure processing performance, but low strength.

Delivery status of 08 # steel:
Delivery shall be made in the condition of no heat treatment or heat treatment (annealing, normalizing or high temperature tempering). If delivery is required in heat treatment state, it shall be indicated in the contract, otherwise, it shall be delivered without heat treatment.

08 # steel heat treatment specification:
Normalizing 930℃, 45min, air cooling; Metallographic structure: ferrite + a small amount of pearlite.

Mechanical properties of 08 # steel:
Tensile strength σb (MPa)≥325(33)
Yield strength σs (MPa)≥195(20)
elongation δ5 (％)≥33
Reduction of area ψ(％)≥60
Hardness without heat treatment ≤ 131HB

Application scope of 08 # steel:
08 # steel is a very soft carbon steel with very low strength and hardness, but very high toughness and plasticity. It has good cold working performance and welding performance such as deep drawing, drawing, bending and upsetting. However, there is aging sensitivity, and the hardenability is extremely low. It is used to manufacture anchor bolts, ploughshare, chimney, roof panel, rivets, low-carbon steel wire, sheet, welded pipe, pull rod, hook, bracket, welded structure, etc.