24 July 2021 Spring Steel Wire
65Mn Spring Steel Bar
65Mn is a common spring steel in Chinese standards. After heat treatment and cold drawing hardening, the strength is relatively high, and it has a certain degree of flexibility and plasticity.
Under the same surface condition and complete hardening, the fatigue limit is equivalent to that of multicolored alloy springs. However, the hardenability is very poor, and it is mainly used for small-sized springs, such as pressure regulating springs, force measuring springs, round and square spiral springs on general machinery, or drawn steel wires as springs on small machinery.
Chemical Composition:
| C(％) | Si(％) | Mn(％) | P(％) | S(％) | Cr(％) | Ni(％) | Cu(%) |
|---|---|---|---|---|---|---|---|
| 0.62-0.70 | 0.17-0.37 | 0.90-1.20 | ≤0.025 | ≤0.025 | ≤0.25 | ≤0.25 | ≤0.25 |
Mechanical Properties：
| Tensile Strength σb (MPa): | Yield Strength σ0.2 (MPa): | Elongation δ5 (%): | Reduction of area ψ (%): | Hardness: |
|---|---|---|---|---|
| ≥ 980 (130) | ≥ 720 (120) | ≥ 14 | ≥ 30 | ≤ 302HB |
Equivalent Grade:
| USA | Germany | China | Japan | France | England | Italy | Poland | ISO | Austria | Sweden | Spain |
|---|---|---|---|---|---|---|---|---|---|---|---|
| AISI/SAE/ASTM/UNS | DIN,WNr | GB | JIS | AFNOR | BS | UNI | PN | ISO | ONORM | SS | UNE |
| 1066 | 65Mn | 080A67 |
Equivalent Grade Chemical Composition:
| Chemical Composition % | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Grade | C | Si | Mn | P (≤) | S (≤) | Cr | Ni (≤) | Cu (≤) | Mo | V |
| 65Mn | 0.62-0.70 | 0.17-0.37 | 0.90-1.20 | 0.030 | 0.030 | ≤ 0.25 | 0.35 | 0.25 | – | – |
| 1065 | 0.60-0.70 | 0.60-0.90 | 0.040 | 0.050 | – | – | (0.20) | – | – | |
| 1075 | 0.70-0.80 | 0.40-0.70 | 0.040 | 0.050 | – | – | (0.20) | – | – | |
| 1095 | 0.90-1.03 | 0.30-0.50 | 0.040 | 0.050 | – | – | (0.20) | – | – | |
| 5160 | 0.56-0.61 | 0.15-0.35 | 0.75-1.00 | 0.035 | 0.040 | 0.70-0.90 | – | (0.30) | – | – |
| SK5 | 0.80-0.90 | 0.10-0.35 | 0.10-0.50 | 0.030 | 0.030 | 0.30 | 0.25 | 0.25 | – | – |
| 8Cr13Mov | 0.70-0.80 | 1.00 | 1.00 | 0.040 | 0.030 | 13.00-14.50 | 0.60 | 0.10-0.30 | 0.10-0.25 | |
Heat treatment and specifications:
Quenching 830℃±20℃, oil cooling; tempering 540℃±50℃ (for special needs, ±30℃).
Critical point temperature (approximate value) Ac1=726℃, Ac3=765℃, Ar3=741℃, Ar1=689℃, Ms=270℃.
Normalizing specification: temperature 810±10℃, air cooling.
Quenching and tempering specifications: quenching temperature 830±10℃, oil cooling; tempering temperature 540℃±10℃, water and oil cooling.
Heat Treatment Suggestion:
65Mn low alloy round steel must have high elastic limit and high yield ratio to avoid permanent deformation of spring steel under high load; at the same time, it also requires good hardenability and low decarburization sensitivity to make elastic The limit is greatly reduced; as well as good surface quality, easy processing and forming in cold and hot conditions and good heat treatment processability.
The heat treatment process of hot-formed spring steel formed in a hot state. Most of the spring steel formed by this method is a combination of hot forming and heat treatment, while most of the coil spring steel is heat treated after hot forming. The heat treatment method of this kind of spring steel is quenching + intermediate temperature tempering, and the structure after heat treatment is tempered troostite. This kind of organization has a high elastic limit and a high yield limit, and has a certain degree of toughness.
Adopt brand-new concepts and methods, and innovatively develop stability control technology. Carefully analyze the formation mechanism of "rolling, tail-flicking" and other problems that are most likely to occur in this "0.4 second" time, so as to reduce roll damage. , Reduce tail deviation and other aspects of work, after more than 3 years of software program development, tracking test, evaluation, analysis to determine reasonable process parameters.
The strength, hardness, elasticity and hardenability of 65Mn steel plate are higher than that of No. 65 steel. It has the tendency of overheating sensitivity and temper brittleness, and the tendency of water quenching to form cracks. Machinability in the annealed state is acceptable, cold deformation plasticity is low, and weldability is poor. Medium-loaded leaf springs, coil springs with a diameter of 7-20mm and spring washers. Spring rings. High wear resistance parts, such as grinding machine spindles, spring chucks, precision machine tool screws, cutters, collars on spiral roller bearings, railway rails, etc.
Delivery Status:
Hot-rolled steel is delivered in a heat-treated or non-heat-treated state, and cold-drawn steel is delivered in a heat-treated state. (2.0-16)*1250*C Laiwu Steel/Hot Coil/Hot Plate