A heat treatment method for improving low-temperature impact toughness of bar
A technology of low-temperature impact toughness and heat treatment method, which is applied in heat treatment furnaces, heat treatment equipment, furnaces, etc., can solve problems such as uneven structure and lack of hardening, and achieve improved strength and low-temperature toughness, improved hardenability, and good mechanical properties Effect
- Summary
- Abstract
- Description
- Claims
- Application Information
AI Technical Summary
Problems solved by technology
Method used
Image
Examples
Embodiment 1
[0017] 1) The internal control chemical composition of bonded steel bars: C: 0.41%, Si: 0.29%, Mn: 0.92%, S: 0.004%, P: 0.012%, Cr: 0.95%, Mo: 0.18%, Fe balance .
[0018] 2) Rough rolling and finishing rolling are carried out on the slab of the above composition after conventional heating, the rolling specification is Φ56mm, and the final rolling temperature is controlled at: 850-900°C;
[0019] 3) Place hot-rolled large-size bars or heat-treated workpieces in a heat-treatment furnace at 840-860°C for heating. According to the heat-treatment experience of different specifications, determine the holding time for 90-120 minutes; then use moderate oil cooling and quenching to heat the workpiece Take it out from the quenching furnace and put it into oil (room temperature), cool for 3 to 10 minutes, so that the temperature of the workpiece drops to the range of Ms (measured at phase transition point 320°C) to 200°C (different from the conventional quenching process to room tempera...
Embodiment 2
[0022] 1) Internal control chemical composition of bonded steel bars: C: 0.40%, Si: 0.24%, Mn: 0.90%, S: 0.003%, P: 0.013%, Cr: 1.0%, Mo: 0.18%, Fe balance .
[0023] 2) Rough rolling and finishing rolling are carried out on the slab of the above composition after conventional heating, the rolling specification is Φ56mm, and the final rolling temperature is controlled at: 850-900°C;
[0024] 3) Place hot-rolled large-size bars or heat-treated workpieces in a heat treatment furnace at 860°C for heating. According to the heat treatment experience of different specifications, determine the holding time for 90-120 minutes; Take it out and put it in oil (at room temperature), cool for 2.5 minutes, so that the temperature of the workpiece drops to the range of Ms (measured at the phase transition point of 320°C) to 150°C, and then take it out quickly;
[0025] 4) Tempering process: put the moderately quenched bar or workpiece in a tempering furnace at 640°C, keep it warm for 120min...
Embodiment 3
[0027] 1) Internal control chemical composition of bonded steel bars: C: 0.40%, Si: 0.22%, Mn: 0.90%, S: 0.005%, P: 0.010%, Cr: 1.0%, Mo: 0.18%, Fe balance .
[0028] 2) Rough rolling and finishing rolling are carried out on the slab of the above composition after conventional heating, the rolling specification is Φ47mm, and the final rolling temperature is controlled at: 850-900°C;
[0029] 3) Place hot-rolled large-size bars or heat-treated workpieces in a heat-treatment furnace at 840-860°C for heating. According to the heat-treatment experience of different specifications, determine the holding time for 90-120 minutes; then use moderate oil cooling and quenching to heat the workpiece Take it out from the quenching furnace and put it into the oil (room temperature), cool for 3-10 minutes, make the temperature of the workpiece drop to the range of Ms (measured at the phase transition point 320°C) to 100°C, and then take it out quickly;
[0030] 4) Tempering process: put the...
PUM
| Property | Measurement | Unit |
|---|---|---|
| tensile strength | aaaaa | aaaaa |
| yield strength | aaaaa | aaaaa |
| impact absorption energy | aaaaa | aaaaa |
Abstract
Description
Claims
Application Information
Login to View More