Biodegradable medical low-zinc magnesium alloy plate as well as preparation method and application thereof

Abstract

The invention provides a biodegradable medical low-zinc magnesium alloy plate as well as a preparation method and application thereof, and belongs to the technical field of alloy materials. According to the method, the low-zinc magnesium alloy cast ingot is used as a raw material, and the good mechanical property and the biodegradability of the low-zinc magnesium alloy can be improved by controlling the rolling temperature, speed and deformation factors of the plate, so that the in-vivo application feasibility of the magnesium-zinc alloy is realized. After the low-zinc magnesium alloy is implanted into a human body, the low-zinc magnesium alloy can bear the mechanical strength of human tissues, and in addition, the low-zinc magnesium alloy also meets the time requirement of slow degradation. Compared with other treatment modes, the preparation method disclosed by the invention adopts a conventional high-temperature heat treatment rolling mode, has the characteristics of simplicity in operation, high rolling efficiency, batch production, low cost, remarkable benefit and the like, further makes up for the shortages of other alloys in the aspects of mechanics, degradability and biocompatibility, and has extremely high application value.

Description

Technical Field

[0001] The present invention relates to the technical field of alloy materials, and in particular to a biodegradable medical low-zinc-magnesium alloy plate, a preparation method thereof, and an application thereof. Background Art

[0002] Magnesium, a commonly used metal implant material in today's medical field, offers numerous unique advantages. First, magnesium is an essential trace element for the human body, playing a crucial role in neuroregulation and immune metabolism. Second, compared to other metal implants, magnesium possesses excellent biocompatibility. Its most significant advantage is its biodegradability, meaning it self-degrades in the human body, thus avoiding the medical expense and physical pain associated with secondary surgical removal of conventional non-degradable metals. Furthermore, the addition of zinc, another essential trace element, can enhance the rate and capacity of cell division, providing nutrients to the injured area.

[0003] However, existing medical magnesium-zinc alloys (such as low-zinc magnesium alloys with a zinc content of 0.2-0.5 wt.%) suffer from insufficient mechanical strength when used directly as biodegradable implant materials. Furthermore, these alloys exhibit a relatively rapid corrosion degradation rate in vivo, making them difficult to meet the demands of actual human tissue repair. Summary of the Invention

[0004] In view of this, the present invention aims to provide a biodegradable medical low-zinc-magnesium alloy sheet, its preparation method, and its application. The biodegradable medical low-zinc-magnesium alloy sheet prepared by the present invention can achieve the good mechanical properties of low-zinc-magnesium alloys and biodegradability suitable for in vivo use, thereby realizing the feasibility of in vivo application of magnesium-zinc alloys.

[0005] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions:

[0006] The present invention provides a method for preparing a biodegradable medical low-zinc-magnesium alloy sheet, comprising the following steps:

[0007] Providing a low-zinc-magnesium alloy ingot with a zinc content of 0.2-0.5wt.%;

[0008] heat-treating the low-zinc-magnesium alloy ingot to obtain a heat-treated low-zinc-magnesium alloy ingot;

[0009] The heat-treated low-zinc-magnesium alloy ingot is subjected to multi-pass rolling to obtain a biodegradable medical low-zinc-magnesium alloy plate; the multi-pass rolling is ≥6 passes; the temperature of the multi-pass rolling is 200-350°C; and the deformation of each pass during the multi-pass rolling is independently 10-40%.

[0010] Preferably, the low-zinc-magnesium alloy ingot has a thickness of 15 to 30 mm, a length of 20 to 30 mm, and a width of 20 to 30 mm.

[0011] Preferably, the heat treatment temperature is 200-350° C., and the holding time is 2-6 hours.

[0012] Preferably, the holding time of the first pass in the multi-pass rolling is 10 to 30 minutes.

[0013] Preferably, the roller speed of the multi-pass rolling is 500-2000 r / min.

[0014] Preferably, the rolling rate of the multi-pass rolling is 2 to 10 m / min.

[0015] The present invention provides a biodegradable medical low-zinc-magnesium alloy plate prepared by the above preparation method.

[0016] Preferably, the biodegradable medical low-zinc-magnesium alloy sheet has a thickness of 1 to 5 mm.

[0017] The present invention provides the use of the above-mentioned biodegradable medical low-zinc-magnesium alloy plate in the preparation of degradable implant materials.

[0018] The present invention provides a method for preparing a biodegradable medical low-zinc-magnesium alloy sheet, comprising the following steps: providing a low-zinc-magnesium alloy ingot having a zinc content of 0.2 to 0.5 wt.%; heat-treating the low-zinc-magnesium alloy ingot to obtain a heat-treated low-zinc-magnesium alloy ingot; and subjecting the heat-treated low-zinc-magnesium alloy ingot to multi-pass rolling to obtain a biodegradable medical low-zinc-magnesium alloy sheet; the multi-pass rolling is performed for ≥6 passes; the temperature of the multi-pass rolling is 200 to 350°C; and the deformation of each pass during the multi-pass rolling is independently 10 to 40%. The present invention uses the low-zinc-magnesium alloy ingot as raw material and, by controlling the sheet rolling temperature, rate, and deformation, achieves excellent mechanical properties and enhanced biodegradability of the low-zinc-magnesium alloy, thereby realizing the feasibility of in vivo application of the magnesium-zinc alloy. During the multi-pass rolling process, dynamic recrystallization during the cumulative plastic deformation process can produce a fine and uniform microstructure, while simultaneously improving mechanical properties and achieving slow degradation. Once implanted, this low-zinc-magnesium alloy can withstand the mechanical strength of human tissue while also meeting the time requirements for slow degradation. Compared to other processing methods, the preparation method of the present invention utilizes conventional high-temperature heat treatment and rolling, offering advantages such as simple operation, high rolling efficiency, mass production, low cost, and significant benefits. Furthermore, it overcomes the shortcomings of other alloys in mechanical properties, degradation, and biocompatibility, thus possessing extremely high application value.

[0019] At the same time, the preparation method provided by the present invention has low equipment requirements and low operation difficulty, and the obtained magnesium-zinc alloy material has excellent mechanical properties and is suitable for market promotion and application. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is a metallographic image of the rolled surface of the medical low-zinc biodegradable magnesium alloy sheet obtained in Example 1;

[0021] Figure 2 This is a metallographic image of the rolled surface of the medical low-zinc biodegradable magnesium alloy sheet obtained in Example 2;

[0022] Figure 3 is the corrosion rate test result;

[0023] Figure 4 Mechanical properties test results. DETAILED DESCRIPTION

[0024] The present invention provides a method for preparing a biodegradable medical low-zinc-magnesium alloy sheet, comprising the following steps:

[0025] Providing a low-zinc-magnesium alloy ingot with a zinc content of 0.2-0.5wt.%;

[0026] heat-treating the low-zinc-magnesium alloy ingot to obtain a heat-treated low-zinc-magnesium alloy ingot;

[0027] The heat-treated low-zinc-magnesium alloy ingot is subjected to multiple rolling processes to obtain a biodegradable medical low-zinc-magnesium alloy plate.

[0028] The present invention provides a low zinc-magnesium alloy ingot with a zinc content of 0.2 to 0.5 wt.%. In the present invention, the zinc content in the low zinc-magnesium alloy ingot is 0.2 to 0.5 wt.%, preferably 0.3 to 0.4 wt.%, and the balance is magnesium. In the present invention, the thickness of the low zinc-magnesium alloy ingot is preferably 15 to 30 mm, specifically 15 mm, 20 mm, 25 mm or 30 mm; the length is preferably 20 to 30 mm, specifically 20 mm, 25 mm or 30 mm; the width is preferably 20 to 30 mm, specifically 20 mm, 25 mm or 30 mm. The present invention has no special requirements for the preparation method of the low zinc-magnesium alloy ingot, and the low zinc-magnesium alloy ingot with the above-mentioned zinc content can be prepared using methods well known in the art.

[0029] Prior to the heat treatment, the low-zinc-magnesium alloy ingot is preferably pretreated. The pretreatment preferably includes grinding, polishing, cleaning, and drying in sequence. The present invention has no particular requirements for the grinding, polishing, cleaning, and drying, and any grinding, polishing, cleaning, and drying methods familiar to those skilled in the art may be used.

[0030] The present invention heat treats the low-zinc-magnesium alloy ingot to obtain a heat-treated low-zinc-magnesium alloy ingot. In the present invention, the heat treatment atmosphere is preferably argon or a vacuum atmosphere; in the present invention, the heat treatment temperature is preferably 200-350°C, more preferably 250-300°C. In the present invention, the heat treatment holding time is 2-6 hours, more preferably 3-5 hours, and even more preferably 4 hours. Through the heat treatment, the present invention can homogenize the alloy structure and achieve a preheating effect.

[0031] After obtaining the heat-treated low-zinc-magnesium alloy ingot, the present invention performs multi-pass rolling on the heat-treated low-zinc-magnesium alloy ingot to obtain a biodegradable medical low-zinc-magnesium alloy sheet. In the present invention, the multi-pass rolling is performed for 6 or more passes, specifically 6, 7, or 8 passes; the temperature of the multi-pass rolling is 200-350°C, preferably 250-300°C; and the deformation of each pass during the multi-pass rolling is independently 10-40%, preferably 25%, specifically 10%, 15%, 20%, 25%, or 40%.

[0032] In the present invention, the holding time of the first pass in the multi-pass rolling is preferably 10 to 30 minutes, more preferably 15 to 25 minutes, and even more preferably 20 minutes.

[0033] In the present invention, the rolling rate of the multi-pass rolling is preferably 2 to 10 m / min, more preferably 8 to 10 m / min.

[0034] In the present invention, the rotation speed of the multi-pass rolling is preferably 500-2000 r / min, more preferably 1000-1500 r / min. By controlling the roller rotation speed of the multi-pass rolling, the present invention can regulate the dynamic recrystallization process during the plastic deformation process, thereby promoting the formation of a fine and uniform microstructure.

[0035] The present invention provides a biodegradable medical low-zinc-magnesium alloy plate prepared by the above preparation method.

[0036] In the present invention, the thickness of the biodegradable medical low zinc-magnesium alloy sheet is preferably 1 to 5 mm, specifically 1 mm, 2 mm, 3 mm, 4 mm or 5 mm.

[0037] The present invention provides the use of the above-mentioned biodegradable medical low-zinc-magnesium alloy sheet in the preparation of a degradable implant material. In the present invention, the implant material is preferably a bone repair material, specifically preferably a bone plate, bone nail or wire anchor.

[0038] The biodegradable medical low-zinc-magnesium alloy sheet provided by the present invention, its preparation method and application are described in detail below with reference to the examples, but they should not be construed as limiting the scope of protection of the present invention.

[0039] Example 1

[0040] A low-zinc (0.3 wt.%) magnesium alloy ingot with a thickness of 30 mm and a length and width of 20 to 30 mm was prepared and pre-treated by grinding, polishing, cleaning and drying.

[0041] The low zinc-magnesium alloy ingot is heated and kept at 350° C. for 2 hours to obtain a heat-treated low zinc-magnesium alloy ingot;

[0042] The heat-treated low-zinc-magnesium alloy ingot was subjected to multi-pass rolling, with a rolling rate of 8 m / min, 6 rolling passes, a rolling temperature of 350°C, a holding time of 10 min for the first pass, and a deformation of 30% for each rolling, to obtain a biodegradable medical low-zinc-magnesium alloy sheet with a thickness of 3.5 mm.

[0043] Figure 1 This is a metallographic image of the rolled surface of the medical low-zinc biodegradable magnesium alloy plate obtained in Example 1. Obvious dynamically recrystallized grains can be seen in the image. The average grain size is 6.29 μm, and the grains are distributed throughout the entire rolled surface.

[0044] Example 2

[0045] A low-zinc (0.5 wt.%) magnesium alloy ingot with a thickness of 30 mm and a length and width of 20 to 30 mm was prepared and pre-treated by grinding, polishing, cleaning and drying.

[0046] The low zinc-magnesium alloy ingot is heated and kept at 300° C. for 4 hours to obtain a heat-treated low zinc-magnesium alloy ingot;

[0047] The heat-treated low-zinc-magnesium alloy ingot is subjected to multi-pass rolling, with a rolling rate of 10 m / min, 6 rolling passes, a rolling temperature of 300° C., a holding time of 20 min for the first pass, and a deformation of 40% for each rolling, to obtain a biodegradable medical low-zinc-magnesium alloy sheet with a thickness of 1.4 mm.

[0048] Figure 2 This is a metallographic image of the rolled surface of the medical low-zinc biodegradable magnesium alloy plate obtained in Example 2. Obvious dynamically recrystallized grains can be seen in the image, with an average grain size of 5.60 μm. The grain distribution and size are very uniform across the entire rolled surface.

[0049] Comparative Example 1

[0050] A low-zinc (0.5 wt.%) magnesium alloy ingot with a thickness of 10 mm and a length and width of 20 to 30 mm was prepared and pre-treated by grinding, polishing, cleaning and drying.

[0051] The low zinc-magnesium alloy ingot is heated and kept at 100° C. for 6 hours to obtain a heat-treated low zinc-magnesium alloy ingot;

[0052] The heat-treated low-zinc-magnesium alloy ingot was subjected to multi-pass rolling, with a rolling rate of 8 m / min, 5 rolling passes, a rolling temperature of 100° C., a holding time of 10 min for the first pass, and a deformation of 20% for each rolling, to obtain a biodegradable medical low-zinc-magnesium alloy sheet with a thickness of 3.2 mm.

[0053] Comparative Example 2

[0054] A low-zinc (0.1 wt.%) magnesium alloy ingot with a thickness of 15 mm and a length and width of 20 to 30 mm was prepared and pre-treated by grinding, polishing, cleaning and drying.

[0055] The low zinc-magnesium alloy ingot is heated and kept at 300° C. for 4 hours to obtain a heat-treated low zinc-magnesium alloy ingot;

[0056] The heat-treated low-zinc-magnesium alloy ingot was subjected to multi-pass rolling, with a rolling rate of 8 m / min, 4 rolling passes, a rolling temperature of 300°C, a holding time of 1 h for the first pass, and a deformation of 30% for each rolling, to obtain a biodegradable medical low-zinc-magnesium alloy sheet with a thickness of 3.6 mm.

[0057] Comparative Example 3

[0058] A low-zinc (1.5 wt.%) magnesium alloy ingot with a thickness of 30 mm and a length and width of 20 to 30 mm was prepared and pre-treated by grinding, polishing, cleaning and drying.

[0059] The low zinc-magnesium alloy ingot is heated and kept at 500° C. for 5 hours to obtain a heat-treated low zinc-magnesium alloy ingot;

[0060] The heat-treated low-zinc-magnesium alloy ingot is subjected to multi-pass rolling, with a rolling rate of 8 m / min, 3 rolling passes, a rolling temperature of 500°C, a holding time of 30 min for the first pass, and a deformation of 70% for each rolling, to obtain a biodegradable medical low-zinc-magnesium alloy sheet with a thickness of 0.8 mm.

[0061] Performance Testing

[0062] ①Corrosion rate test

[0063] The biodegradable medical low zinc magnesium alloy plates obtained in Examples 1 to 2 and Comparative Examples 1 to 3 were cut into 10 mm*10 mm specimens and immersed in 200 mL of PBS simulated body fluid. The comparison curve of the daily pH value change is shown in FIG. Figure 3 As shown, it can be seen that the pH of the low zinc-magnesium alloy plates of Examples 1-2 is lower than that of the comparative example, which proves that the corrosion resistance of the examples is better than that of the comparative example.

[0064] ② Mechanical properties test

[0065] Figure 4 A comparison of the mechanical properties of the biodegradable medical low-zinc-magnesium alloy sheets obtained in Examples 1 and 2 with those of Comparative Examples 1-3 shows that the mechanical strength of the sheets in the Examples is significantly higher than that of the Comparative Examples, both exceeding 250 MPa, while the mechanical strength of the Comparative Examples is approximately 200 MPa. The difference between the two Examples primarily lies in the strain rate caused by the different rolling conditions, with Example 1 exhibiting superior mechanical strength.

[0066] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as within the scope of protection of the present invention.

Claims

1. A method for preparing a biodegradable medical low zinc-magnesium alloy sheet, characterized in that: The following steps are involved: Providing a low-zinc-magnesium alloy ingot with a zinc content of 0.2-0.5wt.%; heat-treating the low-zinc-magnesium alloy ingot to obtain a heat-treated low-zinc-magnesium alloy ingot; The heat-treated low-zinc-magnesium alloy ingot is subjected to multi-pass rolling to obtain a biodegradable medical low-zinc-magnesium alloy plate; the multi-pass rolling is ≥6 passes; the temperature of the multi-pass rolling is 200-350°C; and the deformation of each pass during the multi-pass rolling is independently 10-40%.

2. The preparation method according to claim 1, characterized in that The low-zinc-magnesium alloy ingot has a thickness of 15 to 30 mm, a length of 20 to 30 mm, and a width of 20 to 30 mm.

3. The preparation method according to claim 1, characterized in that The heat treatment temperature is 200-350° C., and the heat preservation time is 2-6 hours.

4. The preparation method according to claim 1, characterized in that During the multi-pass rolling, the heat preservation time of the first pass is 10 to 30 minutes.

5. The preparation method according to claim 1, characterized in that The roller speed of the multi-pass rolling is 500-2000 r / min.

6. The preparation method according to claim 1 or 5, characterized in that The rolling rate of the multi-pass rolling is 2 to 10 m / min.

7. The biodegradable medical low-zinc-magnesium alloy sheet prepared by the preparation method according to claims 1 to 6.

8. The biodegradable medical low zinc-magnesium alloy sheet according to claim 7, characterized in that: The biodegradable medical low-zinc-magnesium alloy plate has a thickness of 1 to 5 mm.

9. Use of the biodegradable medical low-zinc-magnesium alloy sheet according to claim 7 or 8 in the preparation of degradable implant materials.

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