阅读说明：本技术 一种提高42CrMo锻件超声波检测合格率的制作工艺 (Manufacturing process for improving ultrasonic detection qualification rate of 42CrMo forge piece ) 是由 牛余刚 尚贺军 赵丽美 郑东东 牛余兵 于 2019-12-09 设计创作，主要内容包括：本发明涉及锻件制作技术领域,特别是涉及一种提高42CrMo锻件超声波检测合格率的制作工艺。一种提高42CrMo锻件超声波检测合格率的制作工艺,包括以下的步骤：下料；加热；锻造；正火；粗加工；超声检测；调质；精加工；终检。(1)本发明的有益效果在于,由于采用了本发明的工艺,使得煅件的超声波检测合格率可以达到100%,各项力学性能完全满足技术要求。(The invention relates to the technical field of forging manufacturing, in particular to a manufacturing process for improving the ultrasonic detection qualification rate of a 42CrMo forging. A manufacturing process for improving the ultrasonic detection qualification rate of 42CrMo forgings comprises the following steps: blanking; heating; forging; normalizing; rough machining; ultrasonic detection; tempering; fine processing; and (5) final inspection. (1) The invention has the beneficial effects that the process of the invention is adopted, so that the ultrasonic detection qualification rate of the forged piece can reach 100%, and various mechanical properties completely meet the technical requirements.)

1. A manufacturing process for improving the ultrasonic detection qualification rate of 42CrMo forgings comprises the following steps:

blanking; heating; forging; normalizing; rough machining; ultrasonic detection; tempering; fine processing; and (5) final inspection.

2. The manufacturing process for improving the ultrasonic detection qualification rate of the 42CrMo forged piece as claimed in claim 1, wherein the manufacturing process comprises the following steps: in the blanking step, a continuous casting round billet made of 42CrMo is selected and blanked according to the calculated weight.

3. The manufacturing process of 42CrMo for improving the ultrasonic detection qualification rate of forgings according to claim 1, which is characterized in that: in the heating step, the next blank is heated at the temperature of 1200-1250 ℃, and the temperature is kept for 3-6 h.

4. The manufacturing process for improving the ultrasonic detection qualification rate of the 42CrMo forged piece as claimed in claim 1, wherein the manufacturing process comprises the following steps: in the forging step, forging and forming are carried out, the initial forging temperature is controlled to be 850-1200 ℃, the final forging temperature is controlled to be 780-850 ℃, and the forging ratio is more than or equal to 3.5.

5. The manufacturing process for improving the ultrasonic detection qualification rate of the 42CrMo forged piece as claimed in claim 1, wherein the manufacturing process comprises the following steps: in the normalizing step, the formed forge piece is heated in a heat treatment furnace to 50-100 ℃ above the Ac3 point, heat preservation is carried out according to the temperature of 40-60 mm/h, and air cooling is carried out after the forge piece is taken out of the furnace.

6. The manufacturing process for improving the ultrasonic detection qualification rate of the 42CrMo forged piece as claimed in claim 1, wherein the manufacturing process comprises the following steps: and in the rough machining, roughly machining the normalized forge piece to a specified size according to the designed allowance.

7. The manufacturing process for improving the ultrasonic detection qualification rate of the 42CrMo forged piece as claimed in claim 1, wherein the manufacturing process comprises the following steps: and in ultrasonic detection, performing ultrasonic detection on the roughly machined workpiece according to the GB/T6402-2008 standard.

8. The manufacturing process for improving the ultrasonic detection qualification rate of the forge piece according to claim 1, is characterized in that: quenching and tempering: heating the roughly turned forge piece to 650 ℃ in a heat treatment furnace at a speed of less than or equal to 80 ℃/h, preserving heat according to 60-100 mm/h, then heating to 50-150 ℃ above Ac3 according to power, preserving heat for 1-3 h, adjusting the furnace temperature to 50-120 ℃ above Ac3, preserving heat according to 60-80 mm/h, quenching after discharging, heating the forge piece to 280-400 ℃ after quenching is completed, and preserving heat for 3-5 h; and then heating to 600-650 ℃ at a speed of less than or equal to 60 ℃/h, preserving heat according to 40-60 mm/h, and air cooling after discharging.

9. The manufacturing process for improving the ultrasonic detection yield of the 42CrMo forged piece as claimed in claim 1, comprising the following steps:

(1) blanking: selecting a continuous casting round billet made of 42CrMo, and blanking according to the calculated weight;

(2) in the heating step, heating the next blank at 1200-1250 ℃ for 3-6 h;

(3) in the forging step: forging and forming according to a forging process, wherein the initial forging temperature is controlled to be 850-1200 ℃, the final forging temperature is controlled to be 780-850 ℃, and the forging ratio is more than or equal to 3.5;

(4) in the normalizing step, the formed forge piece is heated in a heat treatment furnace to 50-100 ℃ above the Ac3 point, heat preservation is carried out according to the temperature of 40-60 mm/h, and air cooling is carried out after the forge piece is taken out of the furnace;

(5) rough machining: roughly machining the normalized forged piece to a preset size;

(6) ultrasonic detection: carrying out ultrasonic detection on the roughly machined workpiece according to the GB/T6402-2008 standard;

(7) quenching and tempering: heating the roughly turned forge piece to 650 ℃ in a heat treatment furnace at a speed of less than or equal to 80 ℃/h, preserving heat according to 60-100 mm/h, then heating to 50-150 ℃ above Ac3 according to power, preserving heat for 1-3 h, then adjusting the furnace temperature to 50-120 ℃ above Ac3, preserving heat according to 60-80 mm/h, quenching after discharging, heating the forge piece to 280-400 ℃ after quenching, preserving heat for 3-5 h, then heating to 600-650 ℃ at a speed of less than or equal to 60 ℃/h, preserving heat according to 40-60 mm/h, and air cooling after discharging;

(8) finish machining: carrying out finish machining according to a forge piece delivery drawing; final inspection: and (5) carrying out various detections.

Technical Field

The invention relates to the technical field of forging manufacturing, in particular to a manufacturing process for improving the ultrasonic detection qualification rate of a 42CrMo forging.

Background

The 42CrMo material is an important steel grade as a machine reduction structural part, and for parts made of the steel material, the material is required to have comprehensive mechanical properties of good matching of strength and toughness. In order to enable the material to achieve ideal mechanical properties, ultrasonic detection is often carried out on 42CrMo forgings in the manufacturing process of the 42CrMo forgings, and the condition of low ultrasonic detection qualification rate often occurs in the actual detection process, which results in the rejection and scrapping of products.

In order to improve the ultrasonic detection qualified rate of 42CrMo forgings and improve the internal quality of products, the invention provides a manufacturing process for improving the ultrasonic detection qualified rate of the 42CrMo forgings.

Disclosure of Invention

In order to solve the technical problem, the invention provides a 42CrMo forging manufacturing process for remarkably improving the ultrasonic detection yield.

The invention provides a manufacturing process for improving the ultrasonic detection qualification rate of a forge piece, which comprises the following steps:

blanking; heating; forging; normalizing; rough machining; ultrasonic detection; tempering; fine processing; and (5) final inspection.

Preferably, in the step, in the blanking process, a continuous casting round billet made of 42CrMo/42CrMo4 is selected, and blanking is carried out according to the calculated weight.

In the heating step, the next blank is heated according to the heating specification, the heating temperature is 1200-1250 ℃, and the temperature is kept for 3-6 h.

In the forging step: forging and forming are carried out according to a forging process, the initial forging temperature is controlled to be 850-1200 ℃, the final forging temperature is controlled to be 780-850 ℃, and the forging ratio is more than or equal to 3.5.

In the normalizing step, the formed forge piece is heated in a heat treatment furnace to 50-100 ℃ above the Ac3 point, heat preservation is carried out according to the temperature of 40-60 mm/h, and air cooling is carried out after the forge piece is taken out of the furnace.

Rough machining: and (4) roughly machining the normalized forged piece to a specified size according to the designed allowance.

Ultrasonic detection: and carrying out ultrasonic detection on the roughly machined workpiece according to the GB/T6402-2008 standard.

Quenching and tempering: heating the roughly turned forge piece to 650 ℃ in a heat treatment furnace at a speed of less than or equal to 80 ℃/h, preserving heat according to 60-100 mm/h, then heating to 50-150 ℃ above Ac3 according to power, preserving heat for 1-3 h, adjusting the furnace temperature to 50-120 ℃ above Ac3, preserving heat according to 60-80 mm/h, quenching after discharging, heating the forge piece to 280-400 ℃ after quenching is completed, and preserving heat for 3-5 h; and then heating to 600-650 ℃ at a speed of less than or equal to 60 ℃/h, preserving heat according to 40-60 mm/h, and air cooling after discharging.

As an optimization of the invention, the manufacturing process for improving the ultrasonic detection qualification rate of the forge piece comprises the following steps:

(1) blanking: selecting a continuous casting round billet made of 42CrMo/42CrMo4, and blanking according to the calculated weight;

(2) in the heating step, the next blank is heated according to a heating specification, the heating temperature is 1200-1250 ℃, and the temperature is kept for 3-6 hours;

(3) in the forging step: forging and forming according to a forging process, wherein the initial forging temperature is controlled to be 850-1200 ℃, the final forging temperature is controlled to be 780-850 ℃, and the forging ratio is more than or equal to 3.5;

(4) in the normalizing step, the formed forge piece is heated in a heat treatment furnace to 50-100 ℃ above the Ac3 point, heat preservation is carried out according to the temperature of 40-60 mm/h, and air cooling is carried out after the forge piece is taken out of the furnace;

(5) rough machining: roughly machining the normalized forged piece to a preset size;

(6) ultrasonic detection: carrying out ultrasonic detection on the roughly machined workpiece according to the GB/T6402-2008 standard;

(7) quenching and tempering: heating the roughly turned forge piece to 650 ℃ in a heat treatment furnace at a speed of less than or equal to 80 ℃/h, preserving heat according to 60-100 mm/h, then heating to 50-150 ℃ above Ac3 according to power, preserving heat for 1-3 h, then adjusting the furnace temperature to 50-120 ℃ above Ac3, preserving heat according to 60-80 mm/h, quenching after discharging, heating the forge piece to 280-400 ℃ after quenching, preserving heat for 3-5 h, then heating to 600-650 ℃ at a speed of less than or equal to 60 ℃/h, preserving heat according to 40-60 mm/h, and air cooling after discharging;

(8) finish machining: carrying out finish machining according to a forge piece delivery drawing; final inspection: and carrying out various detections according to the requirements of the client.

The invention has the beneficial effects that:

compared with the prior art, the method has the advantages that the ultrasonic detection qualified rate of the forged piece can reach 100% due to the adoption of the process, and various mechanical properties completely meet the technical requirements.

Detailed Description

The present invention will be further described with reference to specific examples so that those skilled in the art may better understand the present invention, but the present invention is not limited thereto.