Additive manufacturing method for ultrahigh-strength steel-stainless steel interlayer heterogeneous structural part

Abstract

The invention belongs to the technical field of additive manufacturing, and particularly relates to an additive manufacturing method of an ultrahigh-strength steel-stainless steel interlayer heterogeneous structural part. Comprising the following steps that (1) a model is obtained, and an additive model is designed according to performance requirements needed by a structural part; (2) additive preparation is conducted, specifically, the type and specification of a base plate are selected, mechanical grinding and welding wire filling are conducted on the base plate, an additive path is planned according to the model, and a robot walking program is written; and (3) material adding is started, the optimal technological parameters are matched according to the planned material adding path, and material adding of the structural part is started and completed. The ultrahigh-strength steel-stainless steel heterostructure part obtained through the method has the excellent strength-toughness comprehensive mechanical property, the material adding efficiency is high, the interface of the ultrahigh-strength steel-stainless steel heterostructure part is free of the defects of holes, microcracks, unbonding and the like, and the surface quality is excellent.

Description

Technical Field

[0001] The present invention belongs to the technical field of additive manufacturing, and specifically relates to an additive manufacturing method for an ultra-high-strength steel-stainless steel interlayer heterogeneous and heterogeneous structural part. Background Art

[0002] Ultra-high-strength steel materials have high strength and hardness, and stainless steel materials have good toughness. It is difficult for the two single materials to meet the high-strength and high-toughness mechanical properties. Heterogeneous and heterogeneous materials can achieve coordination between different materials. Inspired by the "brick-mud" structure of the mother-of-pearl layer in shells in nature, a heterogeneous and heterogeneous component design between ultra-high-strength steel and stainless steel layers is carried out to achieve "strength-plasticity" synergy.

[0003] Additive manufacturing technology, also known as 3D printing technology, is different from traditional manufacturing models. It realizes the manufacture of complex and precise parts by stacking layer by layer and finely controlling material molding. The technology has strong software interactivity, high design freedom, high production efficiency and good product quality. Therefore, it is widely used in various fields such as engineering machinery, aerospace, and military equipment. With the development of additive technology, it plays an increasingly significant role in the manufacture of complex structural parts. It can be used as the preferred preparation process for heterogeneous and heterogeneous components. At present, the reported research on the preparation of ultra-high-strength steel-stainless steel interlayer heterogeneity by additive manufacturing technology is in the early exploratory stage. Summary of the invention

[0004] The object of the present invention is to provide an additive manufacturing method for ultra-high strength steel-stainless steel interlayer heterogeneous and heterogeneous structural parts.

[0005] The technical solution to achieve the purpose of the present invention is: an additive manufacturing method for ultra-high strength steel-stainless steel interlayer heterogeneous and heterogeneous structural parts, comprising the following steps:

[0006] Step (1): Obtain the model and design the additive model according to the performance requirements of the structural parts;

[0007] Step (2): Additive material preparation, selecting the type and specification of the substrate, mechanically grinding the substrate, filling the welding wire, planning the additive path according to the model and writing the robot walking program;

[0008] Step (3): Start additive manufacturing. According to the planned additive manufacturing path, match the optimal process parameters, start additive manufacturing of the structural parts and complete it.

[0009] Furthermore, the heterogeneous material used in step (1) is a bimetallic material of ultra-high strength steel and stainless steel, and the heterogeneous material is a multi-layer structure, including ultra-high strength steel on the outside and stainless steel on the inside.

[0010] Furthermore, the specific composition of the stainless steel welding wire and the ultra-high strength steel welding wire used in step (2) is as follows:

[0011] The stainless steel welding wire used contains the following components: C 0.023%, Mn 1.90%, Si 0.42%, Cr 19.12%, Ni 12.59%, Mo 2.59%, P 0.009%, S 0.008%, Cu 0.28%, and the balance Fe.

[0012] The ultra-high strength steel welding wire used contains the following components: C 0.015%, Mn 1.39%, Si 0.016%, Cr3.41%, Ni 14.08%, Mo 3.13%, P 0.008%, S 0.006%, Ti 0.54%, Al 0.147%, and the balance Fe.

[0013] Furthermore, the diameter of the stainless steel welding wire used in step (2) is 1.20 mm, the diameter of the ultra-high strength steel welding wire is 1.60 mm, and the additive path used is a reciprocating type as a whole. The welding gun is switched according to different structures to achieve switching between different materials.

[0014] Furthermore, in step (3), the stainless steel and ultra-high strength steel used in the additive process are both processed in a pulse cold metal transition additive mode, the dry extension length is 12.00-16.00 mm, the wire feeding speed is 4.5-5.00 m / min, the welding speed is 5.00 mm / s, and the arc voltage of the stainless steel is 18.20-18.80 V, the welding current is 124.00-130.00 A, and the arc voltage of the ultra-high strength steel is 19.20-19.70 V, and the welding current is 142.00-148.00 A.

[0015] Furthermore, in step (3), the protective gas used for stainless steel during material addition is 98.50% Ar+1.50% O2, and the protective gas used for ultra-high strength steel is 99.99% Ar, and the protective gas flow rate is 18.00-25.00 L / min.

[0016] Compared with the prior art, the present invention has the following significant advantages:

[0017] (1) The additive manufacturing method provided by the present invention has high process controllability and low comprehensive manufacturing cost, does not require excessive post-heat treatment and machining, and meets the requirements for efficient manufacturing of layered heterogeneous material components. The material composition and additive parameters of different layers can be reasonably adjusted according to the requirements, and has good application prospects in the manufacturing of metal components with complex structures;

[0018] (2) The additive manufacturing method provided by the present invention adopts a reciprocating cycle during the additive process, exchanging the arc starting and arc extinguishing positions in each layer, avoiding the height difference of the additive caused by the difference in current in the arc starting and arc extinguishing stages, so that the additive parts have a good appearance. The additive process is a pulse cold metal transition mode. Compared with other arc additive processes, it has the advantages of high efficiency, low heat input, no spatter, strong process stability, and good forming performance. Compared with the cold metal transition mode, the addition of pulse circulation speeds up the wire retraction frequency and improves the heat input, so that the welding wire can be fully fused and the overlap between the welds is better, and the surface flatness and forming quality of the additive parts are further improved;

[0019] (3) The ultra-high strength steel-stainless steel interlayer heterogeneous heterogeneous structural component provided by the present invention combines the excellent properties of ultra-high strength steel and stainless steel respectively. The structural design of strong outside and tough inside realizes the synergistic effect of "strength-toughness", and prepares high-strength and high-toughness ultra-high strength steel-stainless steel interlayer heterogeneous heterogeneous structural components, which has practical necessity and good application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a schematic diagram of a high-strength steel-stainless steel interlayer heterogeneous and heterogeneous structural component according to Example 1 of the present invention.

[0021] Figure 2 This is a physical picture of the high-strength steel-stainless steel interlayer heterogeneous and heterogeneous structural component of Example 1 of the present invention.

[0022] Figure 3 This is a Vickers microhardness diagram of a high-strength steel-stainless steel interlayer heterogeneous and heterogeneous structural component of Example 1 of the present invention. DETAILED DESCRIPTION

[0023] In order to make the technical means, creative features, objectives and effects achieved by the present invention easy to understand, the present invention is further described below in conjunction with specific embodiments.

[0024] Example 1

[0025] like Figure 1 As shown, a schematic diagram of an ultra-high-strength steel-stainless steel interlayer heterogeneous and heterogeneous structural component. In order to retain the strength of the structural component to the greatest extent, a "3+1+3" sandwich structure is adopted. The dark part is ultra-high-strength steel and the light part is stainless steel.

[0026] The ultra-high strength steel-stainless steel interlayer heterogeneous heterogeneous structural component additive experimental substrate of the present invention is 304 stainless steel, the substrate size is 300*300*20mm, the stainless steel welding wire used contains the following components C 0.023%, Mn 1.90%, Si0.42%, Cr 19.12%, Ni 12.59%, Mo 2.59%, P 0.009%, S 0.008%, Cu 0.28%, balance Fe, and the welding wire diameter is 1.20mm. The ultra-high strength steel welding wire used contains the following components C 0.015%, Mn 1.39%, Si0.016%, Cr 3.41%, Ni 14.08%, Mo 3.13%, P 0.008%, S 0.006%, Ti 0.54%, Al 0.147%, balance Fe, and the welding wire diameter is 1.60mm.

[0027] Before the experiment, a grinder was used to remove the oxide film on the surface of the 304 stainless steel substrate until it showed a metallic luster. The ultra-high-strength steel welding wire and the stainless steel welding wire were installed in two VR7000-CMT wire feeders respectively, and the program was written and input into the ABB welding robot to prepare for additive manufacturing.

[0028] The CMT welding machine used for additive equipment is the CMT RCU5000i welding machine of Fonis. The unified program in the corresponding material library of the CMT welding machine is used for automatic matching. The stainless steel and ultra-high strength steel are both processed in pulse cold metal transition additive mode, and the dry extension is 12.00-16.00mm. The additive parameters of stainless steel are set as follows: wire feeding speed is 4.50m / min, welding speed is 5.00mm / s, arc voltage is 18.20~18.80V, welding current is 124.00~130.00A, and the shielding gas used is 98.50%Ar+1. 50% O2, gas flow rate is 20.00L / min; set the additive parameters of ultra-high strength steel: wire feeding speed is 5.00m / min, welding speed is 5.00mm / s, arc voltage is 19.20~19.70V, welding current is 142.00~148.00A, the protective gas used is 99.99% Ar, the gas flow rate is 25.00L / min, and the interlayer reciprocating additive method is used. During additive process, the interlayer temperature is controlled at 100℃. After each layer of additive process, the welding gun is raised by 2mm until the additive process is completed.

[0029] The obtained ultra-high strength steel-stainless steel interlayer heterogeneous and heterogeneous structural parts have high surface flatness and excellent quality, such as Figure 2As shown, after testing, the tensile strength of the samples is between 994.40-1081.39MPa, the elongation is between 14.46-19.43%, the absorbed energy of the U-shaped impact specimen is between 112.29-120.02J, the hardness range of the ultra-high strength steel area is 317.2HV~390.7HV, and the hardness range of the stainless steel area is 176.8HV 0.5 ~202.3HV 0.5 .

Claims

1. An additive manufacturing method for ultra-high strength steel-stainless steel interlayer heterogeneous and heterogeneous structural parts, characterized in that: The steps include: Step (1): Obtain the model and design the additive model according to the performance requirements of the structural parts; Step (2): Additive material preparation, selecting the type and specification of the substrate, mechanically grinding the substrate, filling the welding wire, planning the additive path according to the model and writing the robot walking program; Step (3): Start additive manufacturing. According to the planned additive manufacturing path, match the optimal process parameters, start additive manufacturing of the structural parts and complete it.

2. The method according to claim 1, characterized in that In step (1), the heterogeneous materials used are ultra-high strength steel and stainless steel bimetallic materials, and the heterogeneous materials are multi-layer structures, including ultra-high strength steel on the outside of the additive part and stainless steel on the inside.

3. The method according to claim 2, characterized in that In step (2), the specific composition of the stainless steel welding wire and ultra-high strength steel welding wire used is as follows: The stainless steel welding wire used contains the following components: C 0.023%, Mn 1.90%, Si 0.42%, Cr 19.12%, Ni12.59%, Mo 2.59%, P 0.009%, S 0.008%, Cu 0.28%, and the balance Fe; The ultra-high strength steel welding wire used contains the following components: C 0.015%, Mn 1.39%, Si 0.016%, Cr 3.41%, Ni14.08%, Mo 3.13%, P 0.008%, S 0.006%, Ti 0.54%, Al 0.147%, and the balance Fe.

4. The method according to claim 3, characterized in that In step (2), the diameter of the stainless steel welding wire used is 1.20 mm, the diameter of the ultra-high strength steel welding wire is 1.60 mm, and the additive path used is a reciprocating type as a whole. The welding gun is switched according to different structures to achieve switching between different materials.

5. The method according to claim 4, characterized in that In step (3), the stainless steel and ultra-high strength steel during additive processing are both processed in pulse cold metal transition additive mode, the dry extension length is 12.00-16.00 mm, the wire feeding speed is 4.5-5.00 m / min, the welding speed is 5.00 mm / s, and the arc voltage of stainless steel during additive processing is 18.20-18.80 V, the welding current is 124.00-130.00 A, and the arc voltage of ultra-high strength steel during additive processing is 19.20-19.70 V, and the welding current is 142.00-148.00 A.

6. The method according to claim 5, characterized in that In step (3), the protective gas used for stainless steel during material addition is 98.50% Ar+1.50% O2, and the protective gas used for ultra-high strength steel is 99.99% Ar, and the protective gas flow rate is 18.00-25.00 L / min.

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