CN109482995B - A metal matrix with spherical feature array microstructure and its construction method - Google Patents
A metal matrix with spherical feature array microstructure and its construction method Download PDFInfo
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- CN109482995B CN109482995B CN201811352335.4A CN201811352335A CN109482995B CN 109482995 B CN109482995 B CN 109482995B CN 201811352335 A CN201811352335 A CN 201811352335A CN 109482995 B CN109482995 B CN 109482995B
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
- B23K1/00—Soldering, e.g. brazing, or unsoldering
- B23K1/008—Soldering within a furnace
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- B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
- B23K1/00—Soldering, e.g. brazing, or unsoldering
- B23K1/20—Preliminary treatment of work or areas to be soldered, e.g. in respect of a galvanic coating
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Abstract
本发明公开了一种具有球面特征阵列微结构的金属基体及其构建方法，1)以金属材料为基体，先对试样进行预先热处理：在混合溶液中清洗以去除氧化皮，随后用蒸馏水冲洗，烘干备用；2)在金属基体材料表面均匀涂覆一层钎料；3)在涂覆一层钎料的金属材料表面覆盖上金属模板，该模板上有着一定阵列的孔隙排布，随后将与基体相应材质的金属微珠依次放入金属模板空隙中；4)缓慢取出金属模板，利用钎焊技术，在高真空度和合适的焊接温度下，将金属微珠焊接至金属基体材料表面，形成完整均匀的具有球面特征的微结构。该处理工艺简单，制作成本低，易于规模化生产，所得到的结构与基体具有较高的附着力，在生物医用植入体方面有着重要的应用价值。
The invention discloses a metal matrix with a spherical feature array microstructure and a construction method thereof. 1) Taking a metal material as the matrix, pre-heat treatment is performed on the sample first: washing in a mixed solution to remove oxide scale, and then rinsing with distilled water 2) A layer of brazing filler metal is evenly coated on the surface of the metal base material; 3) A metal template is covered on the surface of the metal material coated with a layer of brazing filler metal, and the template has a certain array of pore arrangements, followed by Put the metal microbeads corresponding to the base material into the gap of the metal template in turn; 4) slowly take out the metal template, and use the brazing technology to weld the metal microbeads to the surface of the metal base material under high vacuum and suitable welding temperature , forming a complete and uniform microstructure with spherical features. The treatment process is simple, the manufacturing cost is low, and large-scale production is easy. The obtained structure has high adhesion to the substrate, and has important application value in biomedical implants.
Description
Technical Field
The invention belongs to the technical field of metal matrix surface treatment, and particularly relates to a metal matrix with a spherical characteristic array microstructure on a metal surface and a construction method thereof. The metal surface with the spherical characteristic array microstructure constructed by the invention has important practical significance for promoting the application of a metal matrix in the fields of biomedicine, aerospace, ships and the like.
Background
The natural bone tissue is composed of near-compact bone and porous cancellous bone, and the surface of the natural bone tissue comprises micron, submicron and nanometer multilevel structures[1]. Based on the principle of bionics, the surface of the implant with the micro-nano structure is closer to the surface structure of natural bone tissues than the smooth surface, and is more favorable for differentiation and osseointegration of bone cells[2-3]. In addition, research shows that the micro-nano structured surface can improve the hydrophilicity of the material surfaceAnd the biological activity ion implantation and the micro-nano structure surface generate a synergistic effect, so that the biocompatibility of the micro-nano structure can be further increased. In view of the above advantages, the implant metal with the micro-nano structure on the surface is a research hotspot of people at present, and has a wider application prospect.
The common biomedical metals comprise titanium alloy, magnesium alloy, cobalt-based alloy and the like, wherein the titanium alloy is mature and wide in application, and the invention is used for designing and constructing the surface microstructure of the common biomedical metal alloy material in a targeted manner. In the published patents, the surface treatment methods of titanium alloys are commonly used such as sand blasting, acid etching, alkali heating, anodic oxidation, etc. However, the surface microstructures constructed by these methods have a certain unevenness, and the surface microstructures all have a large number of angular features, which easily causes a stress concentration phenomenon to occur locally on the implant, thereby causing the effects of reduced bonding strength between the implant and the in vivo cells, an obvious biological rejection phenomenon, and the like.
Disclosure of Invention
The invention aims to provide a metal matrix for preparing a spherical characteristic array microstructure on the surface of the metal matrix and a construction method thereof, so as to solve the problem that a smooth surface is not favorable for adhesion, proliferation, differentiation and osseointegration of osteocytes.
A method for constructing a metal matrix with a spherical feature array microstructure comprises the following steps:
1) taking a metal material as a matrix, firstly carrying out pre-heat treatment on a sample: cleaning in the mixed solution to remove oxide skin, then washing with distilled water, and drying for later use;
2) uniformly coating a layer of brazing filler metal on the surface of a metal base material;
3) covering a metal template on the surface of the metal material coated with a layer of brazing filler metal, wherein the template is provided with a certain array of pore arrangements, and then sequentially placing metal microspheres made of materials corresponding to the matrix into the gaps of the metal template;
4) and slowly taking out the metal template, and welding the metal microspheres to the surface of the metal matrix material by using a brazing technology under high vacuum degree and proper welding temperature to form a complete and uniform microstructure with spherical characteristics.
In the construction method, in the step 1), the metal matrix material is titanium alloy, magnesium alloy, cobalt-based alloy, aluminum alloy or stainless steel.
In the construction method, in the step 2), the used brazing filler metal is conventional brazing filler metal such as Ag72Cu silver-based brazing filler metal, Ti-Zr-Ni-Cu titanium-based brazing filler metal and the like.
In the construction method, in the step 3), the diameters of the microbeads are (0.1-1.0mm, preferably 0.5 mm), the gaps among the microbeads can be set to be 0.1-0.8mm, and the metal mold plate material is stainless steel or titanium alloy.
In the construction method, in the step 4), the welding temperature is 800-890 ℃, the heat preservation time is 5-30 min, and the temperature rise rate is 5-10 ℃/min.
In the construction method, in the step 4), the brazing technical parameters for the Ag72Cu silver-based brazing filler metal are as follows: the vacuum degree is about-0.01 MPa, the temperature is increased to 400 ℃ at the heating rate of 10 ℃/min for heat preservation and dehumidification, then the temperature is increased to 750 ℃ at the heating rate of 5 ℃/min for heat preservation for 5min so as to homogenize the temperature in the furnace, then the temperature is increased to 880 ℃ at the heating rate of 10 ℃/min for heat preservation for 0-20 min, and finally the temperature is slowly cooled to the room temperature at the cooling rate of 10 ℃/min.
The metal substrate with the spherical feature array microstructure is obtained according to the construction method.
The invention provides a method for constructing an array microstructure with spherical characteristics, which takes metals such as titanium alloy, magnesium alloy, cobalt-based alloy and the like as base materials, and uniformly welds a layer of metal microspheres made of corresponding materials on a metal base by a brazing method, thereby constructing a novel surface with the spherical characteristics of the array microstructure, and being beneficial to reducing the phenomena of stress concentration, biological rejection and the like generated in the practical application process. The treatment process is simple, the manufacturing cost is low, the large-scale production is easy, the obtained structure and the matrix have high adhesive force, and the biomedical implant has important application value.
The spherical characteristic array microstructure prepared by the method has the following characteristics:
1) the spherical characteristic array microstructure has certain roughness, and has a bedding effect on the preparation of a micro-nano composite structure.
2) The spherical feature array microstructure has uniform performance, high bonding strength with a base material, and completely avoids stress concentration in the application process of the spherical features.
3) The spherical characteristic array microstructure is used in the fields of biomedical implants and the like.
4) The spherical feature array microstructure can also be used in the field of interface bonding of other composite materials.
Drawings
FIG. 1 is a schematic diagram of a spherical feature array microstructure prepared by the method of example 1 of the present invention;
FIG. 2 is a process flow diagram of a spherical feature array microstructure prepared by the method of example 1 of the present invention;
FIG. 3 shows a spherical feature array microstructure formed after a metal template is used in the method of example 1 of the present invention;
FIG. 4 shows a microstructure of an array of spherical features formed after brazing by the method of example 1 of the present invention.
Detailed Description
The present invention will be described in detail with reference to specific examples.
Example 1
The invention provides a method for constructing an array microstructure with spherical characteristics, which comprises the following steps:
firstly, Ti6Al4V titanium alloy is used as a base material, the base material is processed into the size of 60mm multiplied by 25mm multiplied by 3mm by utilizing linear cutting, No. 1-6 metallographic abrasive paper is sequentially adopted to polish the surface of the base material until no scratch is observed under the naked eye, then the base material is mechanically polished until no obvious scratch is observed under a metallographic microscope, and then the base material is put into a mixed solution (volume ratio: HF: HNO)3：H2O1: 1:2) cleaning for 15s to remove surface oxide skin, then quickly washing with distilled water, and drying for later use.
In a second step, a square area of 25mm by 25mm was scribed in the center of the titanium plate, in which a solder of Ag72Cu was uniformly applied in a layer thickness of 0.3 mm. Covering the metal template with the aperture diameter of 0.5mm and the inter-aperture distance of 0.15mm (the circle center distance is 0.65mm) on the area coated with the brazing filler metal. Titanium beads with a diameter of 0.5mm with the corresponding material were spread over the pore size, and the metal template was then carefully removed. Another titanium plate was covered over the titanium beads and the two titanium plates were secured with a stainless steel dovetail clip.
And thirdly, brazing in a tubular vacuum furnace, wherein the vacuum degree is lower than-0.1 MPa, the temperature is increased to 400 ℃ at the heating rate of 10 ℃/min for heat preservation and dehumidification, then the temperature is increased to 750 ℃ at the heating rate of 5 ℃/min for heat preservation for 5min so as to homogenize the temperature in the furnace, then the temperature is increased to 880 ℃ at the heating rate of 5 ℃/min for heat preservation for 0-20 min, and finally the furnace is slowly cooled to room temperature at the cooling rate of 10 ℃/min.
The Ti6Al4V titanium alloy surface with the spherical characteristic array microstructure can be obtained by the method.
Example 2
The invention provides a method for constructing an array microstructure with spherical characteristics, which comprises the following steps:
firstly, Ti6Al7Nb titanium alloy is used as a base material, the base material is processed into 60mm multiplied by 25mm multiplied by 3mm by linear cutting, No. 1-6 metallographic abrasive paper is adopted to polish the surface of the base material in sequence until no scratch is observed under the naked eye, then the base material is mechanically polished until no obvious scratch is observed under a metallographic microscope, and then the base material is put into a mixed solution (volume ratio: HF: HNO)3：H2O1: 1:2) cleaning for 15s to remove surface oxide skin, then quickly washing with distilled water, and drying for later use. After pretreatment, the specimens were grit blasted for 60 mesh.
In a second step, a square area of 25mm by 25mm was scribed in the center of the titanium plate, in which a solder of Ag72Cu was uniformly applied in a layer thickness of 0.4 mm. And covering a metal template with the aperture diameter of 0.5mm and the inter-aperture distance of 0.15mm on the area coated with the brazing filler metal. Titanium beads with a diameter of 0.5mm with the corresponding material were spread over the pore size, and the metal template was then carefully removed. Another titanium plate was covered over the titanium beads and the two titanium plates were secured with a stainless steel dovetail clip.
Thirdly, brazing in a tubular vacuum furnace, wherein the vacuum degree is lower than-0.1 MPa, the temperature is increased to 400 ℃ at the heating rate of 8 ℃/min for heat preservation and dehumidification, then the temperature is increased to 750 ℃ at the heating rate of 8 ℃/min for heat preservation for 5min so as to homogenize the temperature in the furnace, then the temperature is increased to 880 ℃ at the heating rate of 8 ℃/min for heat preservation for 15min, and finally the furnace is slowly cooled to the room temperature at the cooling rate of 10 ℃/min.
The Ti6Al7Nb titanium alloy surface with 60-mesh sand blasting and spherical characteristic array microstructure can be obtained by the method.
Example 3
The preparation method of the spherical characteristic array microstructure comprises the following steps:
firstly, Ti6Al4V titanium alloy is used as a base material, the base material is processed into the size of 60mm multiplied by 25mm multiplied by 3mm by utilizing linear cutting, No. 1-6 metallographic abrasive paper is sequentially adopted to polish the surface of the base material until no scratch is observed under the naked eye, then the base material is mechanically polished until no obvious scratch is observed under a metallographic microscope, and then the base material is put into a mixed solution (volume ratio: HF: HNO)3：H2O1: 1:2) cleaning for 15s to remove surface oxide skin, then quickly washing with distilled water, and drying for later use. After pretreatment, the sample is subjected to 60-mesh sand blasting treatment, and then the micro-nano secondary composite structure surface is obtained by an acid two-step etching method. The acid two-step etching method comprises the following steps: firstly obtaining a sand blasting surface concave-convex structure on a sample after sand blasting, then, similarly, etching for 60min in 40 wt% sulfuric acid solution at 65 ℃ to further obtain a micro-pit structure, and then, etching for 12h in 1M HCL solution at the solution temperature of 85 ℃.
In a second step, a square area of 25mm by 30mm was scribed in the center of the titanium plate, in which a solder of Ag72Cu was uniformly applied in a layer thickness of 0.5 mm. And covering a metal template with the aperture diameter of 0.6mm and the inter-aperture distance of 0.2mm on the area coated with the brazing filler metal. Titanium beads with a diameter of 0.6mm with the corresponding material were spread over the pore size, and the metal template was then carefully removed. Another titanium plate was covered over the titanium beads and the two titanium plates were secured with a stainless steel dovetail clip.
Thirdly, brazing in a tubular vacuum furnace, wherein the vacuum degree is lower than-0.1 MPa, the temperature is increased to 400 ℃ at the heating rate of 8 ℃/min for heat preservation and dehumidification, then the temperature is increased to 750 ℃ at the heating rate of 8 ℃/min for heat preservation for 5min so as to homogenize the temperature in the furnace, then the temperature is increased to 880 ℃ at the heating rate of 8 ℃/min for heat preservation for 15min, and finally the furnace is slowly cooled to the room temperature at the cooling rate of 10 ℃/min.
The Ti6Al4V titanium alloy surface with 60-mesh sand blasting and acid two-step etching and spherical characteristic array microstructure can be obtained by the method.
Example 4
The preparation method of the spherical characteristic array microstructure comprises the following steps:
firstly, Ti6Al7Nb titanium alloy is used as a base material, the base material is processed into 60mm multiplied by 25mm multiplied by 4mm by linear cutting, No. 1-6 metallographic abrasive paper is adopted to polish the surface of the base material in sequence until no scratch is observed under the naked eye, then the base material is mechanically polished until no obvious scratch is observed under a metallographic microscope, and then the base material is put into a mixed solution (volume ratio: HF: HNO)3：H2O1: 1:2) cleaning for 15s to remove surface oxide skin, then quickly washing with distilled water, and drying for later use.
In a second step, a square area of 25mm by 25mm was scribed in the center of the titanium plate, in which a solder of Ag72Cu was uniformly applied in a layer thickness of 0.2 mm. And covering a metal template with the aperture diameter of 0.6mm and the inter-aperture distance of 0.2mm on the area coated with the brazing filler metal. Titanium beads with a diameter of 0.6mm with the corresponding material were spread over the pore size, and the metal template was then carefully removed. Another titanium plate was covered over the titanium beads and the two titanium plates were secured with a stainless steel dovetail clip.
Thirdly, brazing in a tubular vacuum furnace, wherein the vacuum degree is lower than-0.1 MPa, the temperature is increased to 400 ℃ at the heating rate of 8 ℃/min for heat preservation and dehumidification, then the temperature is increased to 750 ℃ at the heating rate of 8 ℃/min for heat preservation for 5min so as to homogenize the temperature in the furnace, then the temperature is increased to 880 ℃ at the heating rate of 5 ℃/min for heat preservation for 10min, and finally the furnace is slowly cooled to the room temperature at the cooling rate of 10 ℃/min.
The Ti6Al7Nb titanium alloy surface containing the titanium bead array microstructure can be obtained by the method.
Example 5
The preparation method of the spherical characteristic array microstructure comprises the following steps:
firstly, using magnesium alloy as a base material, processing the base material into a size of 60mm multiplied by 25mm multiplied by 4mm by utilizing linear cutting, sequentially grinding the surface of the base material by using No. 1-6 metallographic abrasive paper until no scratch is observed under the condition of naked eyes, then mechanically polishing the base material until no obvious scratch is observed under a metallographic microscope, and then adding the base material into a mixed solution (volume ratio: HF: HNO)3：H2O1: 1:2) cleaning for 15s to remove surface oxide skin, then quickly washing with distilled water, and drying for later use. After pretreatment, the sample was subjected to 60 mesh blasting,
secondly, a rectangular area of 40mm multiplied by 25mm is scribed at the center of the magnesium plate, and a Ti-Zr-Ni-Cu brazing filler metal with the thickness of 0.3mm is uniformly coated in the rectangular area. And covering a metal template with the aperture diameter of 0.5mm and the inter-aperture distance of 0.15mm on the area coated with the brazing filler metal. Magnesium beads with a diameter of 0.5mm and corresponding material were spread over the pore diameter, and the metal form was then carefully removed. Another magnesium plate was covered over the titanium beads and the two magnesium plates were secured with a stainless steel dovetail clip.
Thirdly, brazing in a tubular vacuum furnace, wherein the vacuum degree is lower than-0.1 MPa, the temperature is increased to 400 ℃ at the heating rate of 10 ℃/min for heat preservation and dehumidification, then the temperature is increased to 750 ℃ at the heating rate of 5 ℃/min for heat preservation for 5min so as to homogenize the temperature in the furnace, then the temperature is increased to 880 ℃ at the heating rate of 5 ℃/min for heat preservation for 10min, and finally the furnace is slowly cooled to the room temperature at the cooling rate of 10 ℃/min.
The magnesium alloy surface with 60-mesh sand blasting and spherical surface characteristic array microstructure can be obtained according to the method.
It will be understood that modifications and variations can be made by persons skilled in the art in light of the above teachings and all such modifications and variations are intended to be included within the scope of the invention as defined in the appended claims.
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