WO2011091449A1 - A process for producing titanium-magnesium alloy powders and compacts - Google Patents

A process for producing titanium-magnesium alloy powders and compacts Download PDF

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Publication number
WO2011091449A1
WO2011091449A1 PCT/ZA2011/000005 ZA2011000005W WO2011091449A1 WO 2011091449 A1 WO2011091449 A1 WO 2011091449A1 ZA 2011000005 W ZA2011000005 W ZA 2011000005W WO 2011091449 A1 WO2011091449 A1 WO 2011091449A1
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Prior art keywords
powder
titanium
magnesium
sintered product
magnesium alloy
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PCT/ZA2011/000005
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French (fr)
Inventor
Hilda Kundai Chikwanda
Christopher Nyongesa Machio
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Csir
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    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C14/00—Alloys based on titanium
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F9/00—Making metallic powder or suspensions thereof
    • B22F9/02—Making metallic powder or suspensions thereof using physical processes
    • B22F9/04—Making metallic powder or suspensions thereof using physical processes starting from solid material, e.g. by crushing, grinding or milling
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C1/00—Making non-ferrous alloys
    • C22C1/04—Making non-ferrous alloys by powder metallurgy
    • C22C1/045—Alloys based on refractory metals
    • C22C1/0458—Alloys based on titanium, zirconium or hafnium
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F9/00—Making metallic powder or suspensions thereof
    • B22F9/02—Making metallic powder or suspensions thereof using physical processes
    • B22F9/04—Making metallic powder or suspensions thereof using physical processes starting from solid material, e.g. by crushing, grinding or milling
    • B22F2009/041—Making metallic powder or suspensions thereof using physical processes starting from solid material, e.g. by crushing, grinding or milling by mechanical alloying, e.g. blending, milling
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F9/00—Making metallic powder or suspensions thereof
    • B22F9/02—Making metallic powder or suspensions thereof using physical processes
    • B22F9/04—Making metallic powder or suspensions thereof using physical processes starting from solid material, e.g. by crushing, grinding or milling
    • B22F2009/042—Making metallic powder or suspensions thereof using physical processes starting from solid material, e.g. by crushing, grinding or milling using a particular milling fluid
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F2998/00—Supplementary information concerning processes or compositions relating to powder metallurgy
    • B22F2998/10—Processes characterised by the sequence of their steps

Definitions

  • This invention relates to a process for producing a titanium-magnesium alloy powder and to a process to consolidate the produced alloy powder into sintered products.
  • Titanium and many of its alloys are extensively used in aerospace applications due to their high specific strength, superior high temperature performance and excellent corrosion resistance. A reduction in weight of materials used in manufacturing of components for aerospace and automotive applications is desirable. A titanium- magnesium alloy would result in a 15% reduction in component weight when using 11 % magnesium by weight.
  • Titanium-magnesium alloys cannot be produced using conventional casting methods because the two metals are immiscible. No equilibrium processing methods are able to achieve mixing of these two elements in the desired proportions. The reason for this is the significantly lower boiling point of magnesium (1090°C) in relation to the melting point of titanium (1668°C). When attempting to produce a titanium-magnesium alloy by mixing the two elements in the molten state, magnesium is lost through vaporization because it reaches the super vapour state before the titanium has melted.
  • the equilibrium solid solubility of magnesium in titanium is about 0,7% at a temperature of about 890°C.
  • Magnesium and titanium have positive heats of mixing and therefore have very little mutual solubility which makes it difficult to produce titanium-magnesium alloys containing relatively large amounts of magnesium.
  • the titanium-containing powder may include elemental titanium powder and/or titanium oxide powder.
  • the magnesium content of the raw powder mixture may be between five and twenty five weight percent.
  • the magnesium powder may be provided in a stoichiometric excess of about 15% by weight.
  • the initial particle size of the magnesium powder may be between 10 and 150pm and the initial particle size of the titanium-containing powder may be between 10 and 75 pm.
  • a process control agent may be mixed with the titanium-containing powder and magnesium powder prior to the mechanical milling processing step.
  • the process control agent may constitute between one and five weight percent of the raw powder mixture.
  • the process control agent may be selected from the group including: stearic acid, hexane, and ethanol.
  • the process control agent may inhibit excessive cold welding of the powder during milling.
  • the mechanical milling processing step may be a mechanochemical processing step.
  • the mill used may be a high energy ball mill, for example, a Simoloyer CM01- 2L mill.
  • the milling medium may be hardened steel balls having a diameter of between 5mm and 15mm, preferably 5mm.
  • the ball to raw powder mixture ratio may be about 20:1.
  • the milling time may be between 0.5 and 32 hours and the milling may be carried out continuously.
  • the milling step may be carried out in a substantially inert atmosphere, for example, Argon.
  • the process may include an additional separation step during which impurities are removed from the titanium-magnesium alloy powder.
  • the impurities may, for example, be oxides such as magnesium oxide and titanium oxide.
  • the oxides may be removed by leaching the oxides from the titanium-magnesium alloy powder using a suitable leachant and appropriate process conditions.
  • a process for producing a sintered product manufactured from a titanium-magnesium alloy powder produced according to the process described above including at least the steps of: - compacting the alloy powder in a die under pressure to achieve a green product density of at least seventy five percent of the full density of the sintered product; and
  • the full density of the sintered product may be indicated by theoretical density.
  • the compacting step may take place at an elevated temperature, which temperature is below that of the lowest-melting alloy constituent.
  • the green product density may be at least seventy five percent of the full density of the sintered product (as indicated by theoretical density).
  • the sintered product density may be between ninety five and one hundred percent of the theoretical density of the sintered product
  • the thermal processing step may be a sintering step.
  • the sintering step may be carried out in a substantially inert atmosphere.
  • the compacting and thermal processing steps may take place simultaneously.
  • a lubricant may be mixed with the alloy powder prior to compacting.
  • the lubricant may inhibit friction between the powder particles during compaction.
  • the lubricant may constitute between zero and five weight percent of the total alloy powder to be compacted.
  • the lubricant may be selected from the group including: stearic acid, paraffin wax, hexane, and ethanol
  • the die may be lubricated.
  • the die may have a net shape of the required product.
  • the invention extends to a sintered product manufactured by a process as described above.
  • Figure 1 shows a schematic diagram of an embodiment of a process for producing titanium alloy powders in accordance with the present invention.
  • FIG 2 shows a schematic diagram of an embodiment of a process for producing a sintered product manufactured from a titanium-magnesium alloy powder.
  • reference numeral 10 generally indicates a process for producing titanium alloy powders in accordance with the present invention.
  • the process 10 includes a mixing step 12 in which a titanium-containing powder 14 and a magnesium powder 16 are mixed to form a raw powder mixture 18.
  • the raw powder mixture 18 is then subjected to a milling step 20 to convert the raw powder mixture 18 to a titanium-magnesium alloy powder 22.
  • the titanium-containing powder 14 can be elemental titanium powder and/or titanium oxide powder.
  • the magnesium powder 16 is provided in a stoichiometric excess of about 15% by weight.
  • the magnesium content of the raw powder mixture 18 is between five and twenty five weight percent.
  • the reactions taking place during the milling step 20 are as follows:
  • the initial particle size of the magnesium powder 16 is less than 150pm and the initial particle size of the titanium-containing powder 14 is less than 75 pm.
  • a process control agent 24 is mixed with the titanium-containing powder 14 and magnesium powder 16 prior to the milling step 20.
  • the process control agent 24 typically constitutes about between one and five weight percent of the raw powder mixture 18.
  • the process control agent 24 is typically stearic acid.
  • the mill used during the milling step 20 is a Simoloyer CM01-2L high energy ball mill.
  • the milling medium is in the form of hardened steel balls having a diameter of about 5mm with the ball to raw powder mixture 18 ratio being about 20:1.
  • the milling time is between 0.5 and 32 hours, for example, 2, 4, 8, 16 and 24 hours, and the milling is carried out continuously at about 800rpm.
  • the milling step 20 is advantageously carried out in a substantially inert atmosphere, for example, Argon.
  • a separation step 26 during which impurities are removed from the titanium- magnesium alloy powder 22 may follow the milling step 20.
  • the impurities are oxides 28 such as magnesium oxide and titanium oxide.
  • the oxides 28 are removed by leaching the oxides 28 from the titanium-magnesium alloy powder 22 in a platform shaker at about 200 rpm using organic and inorganic acid solutions at temperatures of up to 90°C. The remaining powder 22 is washed with distilled water and dried. Experiments were carried out during which a titanium-magnesium alloy powder was produced.
  • the powders were produced by mechanical milling in a high energy ball mill from the elemental powders of Mg and Ti, except for one in which the oxide of Ti and elemental Mg were used (indicated by * ).
  • the ranges of Mg content of the powders produced is set out below:
  • SPS stand for spark plasma sintering
  • P&S stands for press and sinter.
  • the Mg contents achieved show that new alloys with significant amounts of Mg are being produced.
  • a grade 5 TieAUV alloy has a density of 4.5 g/cm 3 .
  • reference numeral 30 generally indicates a process for producing a sintered product 32 manufactured from the titanium-magnesium alloy powder 22 produced according to the process 10 shown in Figure 1.
  • the alloy powder 22 is compacted in a compacting step 34 in a die under pressure to achieve a green product density of at least seventy five percent of the full density of the alloy powder 22.
  • the die of the compacting step 34 is lubricated by a suitable lubricant and may be a net shape of the required product.
  • the green product 36 is then sintered in a sintering step 38 at a temperature of between 450 and 800 °C to achieve a sintered product density above ninety five percent of the theoretical density of the sintered product 32.
  • the sintering step 38 can optionally be carried out in a substantially inert atmosphere.
  • the magnesium content of the sintered product 32 is between 0.05 and 25 weight percent.
  • the sintered product density is between ninety five and one hundred percent of the theoretical density of the sintered product 32.
  • the compacting step 34 can optionally take place at an elevated temperature, which temperature is below that of the lowest-melting alloy constituent.
  • the green product density is between ninety five and one hundred percent of the theoretical density of the TiMg alloy manufactured from the alloy powder 22.
  • a lubricant 40 may be mixed with the alloy powder 22 prior to the compacting step 34.
  • the lubricant 40 constitutes about between zero and five weight percent of the total alloy powder 22 to be compacted.
  • the lubricant 40 is typically stearic acid.

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Powder Metallurgy (AREA)
  • Manufacture Of Metal Powder And Suspensions Thereof (AREA)

Abstract

The process 10 includes a mixing step 12 in which a titanium-containing powder 14 and a magnesium powder 16 are mixed to form a raw powder mixture 18. The raw powder mixture 18 is then subjected to a milling step 20 to convert the raw powder mixture 18 to a titanium-magnesium alloy powder 22. The titanium-containing powder 14 can be elemental titanium powder and/or titanium oxide powder. In the case where the titanium containing powder is titanium oxide, the magnesium powder 16 is provided in a stoichiometric excess of about 15% by weight. The magnesium content of the raw powder mixture 18 is between five and twenty five weight percent.

Description

A PROCESS FOR PRODUCING TITANIUM-MAGNESIUM ALLOY POWDERS
AND COMPACTS
Field of the Invention
This invention relates to a process for producing a titanium-magnesium alloy powder and to a process to consolidate the produced alloy powder into sintered products.
Background to the Invention
Titanium and many of its alloys are extensively used in aerospace applications due to their high specific strength, superior high temperature performance and excellent corrosion resistance. A reduction in weight of materials used in manufacturing of components for aerospace and automotive applications is desirable. A titanium- magnesium alloy would result in a 15% reduction in component weight when using 11 % magnesium by weight.
Titanium-magnesium alloys, however, cannot be produced using conventional casting methods because the two metals are immiscible. No equilibrium processing methods are able to achieve mixing of these two elements in the desired proportions. The reason for this is the significantly lower boiling point of magnesium (1090°C) in relation to the melting point of titanium (1668°C). When attempting to produce a titanium-magnesium alloy by mixing the two elements in the molten state, magnesium is lost through vaporization because it reaches the super vapour state before the titanium has melted.
In addition, the equilibrium solid solubility of magnesium in titanium is about 0,7% at a temperature of about 890°C. Magnesium and titanium have positive heats of mixing and therefore have very little mutual solubility which makes it difficult to produce titanium-magnesium alloys containing relatively large amounts of magnesium.
The inventors therefore believe that a need exists for providing a "far from equilibrium" and economical process, for producing titanium-magnesium alloy powders with relatively high magnesium content. Summary of the Invention
According to the invention, there is provided a process for producing titanium- magnesium alloy powders, the process including at least the steps of:-
- mixing a titanium-containing powder and a magnesium powder to form a raw powder mixture; and
- subjecting the raw powder mixture to a mechanical milling processing step to convert the raw powder mixture to a titanium-magnesium alloy powder; wherein the magnesium powder is provided in a stoichiometric excess of at least fifteen percent by weight. The titanium-containing powder may include elemental titanium powder and/or titanium oxide powder.
The magnesium content of the raw powder mixture may be between five and twenty five weight percent.
In the event that the titanium containing powder is titanium oxide, the magnesium powder may be provided in a stoichiometric excess of about 15% by weight.
The initial particle size of the magnesium powder may be between 10 and 150pm and the initial particle size of the titanium-containing powder may be between 10 and 75 pm.
A process control agent may be mixed with the titanium-containing powder and magnesium powder prior to the mechanical milling processing step. The process control agent may constitute between one and five weight percent of the raw powder mixture. The process control agent may be selected from the group including: stearic acid, hexane, and ethanol. The process control agent may inhibit excessive cold welding of the powder during milling. The mechanical milling processing step may be a mechanochemical processing step. The mill used may be a high energy ball mill, for example, a Simoloyer CM01- 2L mill.
The milling medium may be hardened steel balls having a diameter of between 5mm and 15mm, preferably 5mm. The ball to raw powder mixture ratio may be about 20:1.
The milling time may be between 0.5 and 32 hours and the milling may be carried out continuously.
The milling step may be carried out in a substantially inert atmosphere, for example, Argon.
The process may include an additional separation step during which impurities are removed from the titanium-magnesium alloy powder. The impurities may, for example, be oxides such as magnesium oxide and titanium oxide. The oxides may be removed by leaching the oxides from the titanium-magnesium alloy powder using a suitable leachant and appropriate process conditions.
According to a further aspect of the invention, there is provided a process for producing a sintered product manufactured from a titanium-magnesium alloy powder produced according to the process described above, the process including at least the steps of: - compacting the alloy powder in a die under pressure to achieve a green product density of at least seventy five percent of the full density of the sintered product; and
- thermally processing the compacted green product at a temperature of between 450 and 800 °C to achieve a sintered product with density above ninety five percent of the theoretical density of the sintered product and wherein the magnesium content of the sintered product is between 0.05 and 25 weight percent.
The full density of the sintered product may be indicated by theoretical density.
The compacting step may take place at an elevated temperature, which temperature is below that of the lowest-melting alloy constituent.
The green product density may be at least seventy five percent of the full density of the sintered product (as indicated by theoretical density).
The sintered product density may be between ninety five and one hundred percent of the theoretical density of the sintered product The thermal processing step may be a sintering step. The sintering step may be carried out in a substantially inert atmosphere.
The compacting and thermal processing steps may take place simultaneously.
A lubricant may be mixed with the alloy powder prior to compacting. The lubricant may inhibit friction between the powder particles during compaction.
The lubricant may constitute between zero and five weight percent of the total alloy powder to be compacted. The lubricant may be selected from the group including: stearic acid, paraffin wax, hexane, and ethanol
The die may be lubricated. The die may have a net shape of the required product. The invention extends to a sintered product manufactured by a process as described above.
Detailed Description of the Invention
The invention will now be described by way of the following non-limiting example with reference to the accompanying representations. In the drawings:
Figure 1 shows a schematic diagram of an embodiment of a process for producing titanium alloy powders in accordance with the present invention; and
Figure 2 shows a schematic diagram of an embodiment of a process for producing a sintered product manufactured from a titanium-magnesium alloy powder. In Figure 1 , reference numeral 10 generally indicates a process for producing titanium alloy powders in accordance with the present invention.
The process 10 includes a mixing step 12 in which a titanium-containing powder 14 and a magnesium powder 16 are mixed to form a raw powder mixture 18.
The raw powder mixture 18 is then subjected to a milling step 20 to convert the raw powder mixture 18 to a titanium-magnesium alloy powder 22.
The titanium-containing powder 14 can be elemental titanium powder and/or titanium oxide powder. In the case where the titanium containing powder is titanium oxide, the magnesium powder 16 is provided in a stoichiometric excess of about 15% by weight.
The magnesium content of the raw powder mixture 18 is between five and twenty five weight percent. Depending on whether titanium or titanium oxide powder is used, the reactions taking place during the milling step 20 are as follows:
Ti + Mg→ TiMg
Ti02 + Mg→ TiMg + Mg & Ti oxides
The initial particle size of the magnesium powder 16 is less than 150pm and the initial particle size of the titanium-containing powder 14 is less than 75 pm.
A process control agent 24 is mixed with the titanium-containing powder 14 and magnesium powder 16 prior to the milling step 20. The process control agent 24 typically constitutes about between one and five weight percent of the raw powder mixture 18. The process control agent 24 is typically stearic acid. The mill used during the milling step 20 is a Simoloyer CM01-2L high energy ball mill. The milling medium is in the form of hardened steel balls having a diameter of about 5mm with the ball to raw powder mixture 18 ratio being about 20:1.
The milling time is between 0.5 and 32 hours, for example, 2, 4, 8, 16 and 24 hours, and the milling is carried out continuously at about 800rpm. The milling step 20 is advantageously carried out in a substantially inert atmosphere, for example, Argon.
A separation step 26 during which impurities are removed from the titanium- magnesium alloy powder 22 may follow the milling step 20. The impurities are oxides 28 such as magnesium oxide and titanium oxide. The oxides 28 are removed by leaching the oxides 28 from the titanium-magnesium alloy powder 22 in a platform shaker at about 200 rpm using organic and inorganic acid solutions at temperatures of up to 90°C. The remaining powder 22 is washed with distilled water and dried. Experiments were carried out during which a titanium-magnesium alloy powder was produced. The powders were produced by mechanical milling in a high energy ball mill from the elemental powders of Mg and Ti, except for one in which the oxide of Ti and elemental Mg were used (indicated by *). The ranges of Mg content of the powders produced is set out below:
Figure imgf000007_0001
Wherein SPS stand for spark plasma sintering and P&S stands for press and sinter.
The Mg contents achieved show that new alloys with significant amounts of Mg are being produced.
Further experiments were carried out in which densities of the sintered alloy compacts were measured. Two different consolidation and sintering methods had been used. The densities of the resulting sintered products are set out in the table below. Here, the alloy powders were produced from elemental Ti and Mg.
Figure imgf000007_0002
The densities obtained when compared to existing grades of Ti alloys, are lower or equal thereto which reflects an overall weight reduction. For example, a grade 5 TieAUV alloy has a density of 4.5 g/cm3.
Referring now to Figure 2, reference numeral 30 generally indicates a process for producing a sintered product 32 manufactured from the titanium-magnesium alloy powder 22 produced according to the process 10 shown in Figure 1.
The alloy powder 22 is compacted in a compacting step 34 in a die under pressure to achieve a green product density of at least seventy five percent of the full density of the alloy powder 22. The die of the compacting step 34 is lubricated by a suitable lubricant and may be a net shape of the required product.
The green product 36 is then sintered in a sintering step 38 at a temperature of between 450 and 800 °C to achieve a sintered product density above ninety five percent of the theoretical density of the sintered product 32. The sintering step 38 can optionally be carried out in a substantially inert atmosphere. The magnesium content of the sintered product 32 is between 0.05 and 25 weight percent. The sintered product density is between ninety five and one hundred percent of the theoretical density of the sintered product 32.
The compacting step 34 can optionally take place at an elevated temperature, which temperature is below that of the lowest-melting alloy constituent. In this case, the green product density is between ninety five and one hundred percent of the theoretical density of the TiMg alloy manufactured from the alloy powder 22.
A lubricant 40 may be mixed with the alloy powder 22 prior to the compacting step 34. The lubricant 40 constitutes about between zero and five weight percent of the total alloy powder 22 to be compacted. The lubricant 40 is typically stearic acid.
It is to be appreciated, that the invention is not limited to any particular embodiment or configuration as hereinbefore generally described or illustrated.

Claims

Claims
1. A process for producing titanium-magnesium alloy powders, the process including at least the steps of:-
- mixing a titanium-containing powder and a magnesium powder to form a raw powder mixture; and
- subjecting the raw powder mixture to a mechanical milling processing step to convert the raw powder mixture to a titanium-magnesium alloy powder; wherein the magnesium powder is provided in a stoichiometric excess of at least fifteen percent by weight.
2. A process as claimed in claim 1 , wherein the titanium-containing powder is selected from: elemental titanium powder and titanium oxide powder.
3. A process as claimed in claim 1 or claim 2, wherein the magnesium content of the raw powder mixture is between five and twenty five weight percent.
4. A process as claimed in claim 2, wherein, when the titanium containing powder is titanium oxide, the magnesium powder is provided in a stoichiometric excess of about 15% by weight.
5. A process as claimed in any one of the preceding claims, wherein the initial particle size of the magnesium powder is between 10 and 150pm and the initial particle size of the titanium-containing powder is between 10 and 75 pm.
6. A process as claimed in any one of the preceding claims, wherein a process control agent is mixed with the titanium-containing powder and magnesium powder prior to the mechanical milling processing step for inhibiting excessive cold welding of the powder during milling.
7. A process as claimed in claim 6, wherein the process control agent constitutes between one and five weight percent of the raw powder mixture.
8. A process as claimed in claim 6 or claim 7, wherein the process control agent is selected from the group including: stearic acid, hexane, and ethanol.
9. A process as claimed in any one of the preceding claims, wherein the mechanical milling processing step is a mechanochemical processing step.
10. A process as claimed in claim 9, wherein the milling medium is in the form of hardened steel balls having a diameter of between 5mm and 15mm, preferably 5mm.
11.A process as claimed in claim 10, wherein the ball to raw powder mixture ratio is about 20:1.
12. A process as claimed in any one of claims 9 to 11 , wherein the milling time is between 0.5 and 32 hours and the milling is carried out continuously.
13. A process as claimed in any one of claims 9 to 12, wherein the milling step is carried out in a substantially inert atmosphere.
14. A process as claimed in any one of the preceding claims, wherein the process includes an additional separation step during which impurities are removed from the titanium-magnesium alloy powder.
15. A process as claimed in claim 14, wherein impurities are removed by leaching them from the titanium-magnesium alloy powder using a suitable leachant and appropriate process conditions.
16. A process for producing a sintered product manufactured from a titanium- magnesium alloy powder produced according to a process as claimed in any one of claims 1 to 15, the process including at least the steps of:
- compacting the alloy powder in a die under pressure to achieve a green product density of at least seventy five percent of the full density of the sintered product; and
- thermally processing the compacted green product at a temperature of between 450 and 800 °C to achieve a sintered product with density above ninety five percent of the theoretical density of the sintered product and wherein the magnesium content of the sintered product is between 0.05 and 25 weight percent.
17. A process as claimed in claim 17, wherein the compacting step takes place at an elevated temperature, which temperature is below that of the lowest- melting alloy constituent.
18. A process as claimed in claim 16 or 17, wherein the green product density is at least seventy five percent of the full density of the sintered product as indicated by theoretical density.
19. A process as claimed in any one of claims 16 to 18, wherein the sintered product density is between ninety five and one hundred percent of the theoretical density of the sintered product
20. A process as claimed in any one of claims 16 to 19, wherein the thermal processing step is a sintering step.
21. A process as claimed in claim 20, wherein sintering step is carried out in a substantially inert atmosphere.
22. A process as claimed in any one of claims 16 to 21 , wherein the compacting and thermal processing steps take place simultaneously.
23. A process as claimed in any one of claims 16 to 22, wherein a lubricant is mixed with the alloy powder prior to compacting.
24. A process as claimed in claim 23, wherein the lubricant constitutes between zero and five weight percent of the total alloy powder to be compacted.
25. A process as claimed in claim 23 or claim 24, wherein the lubricant is selected from the group including: stearic acid, paraffin wax, hexane, and ethanol
26. A process as claimed in any one of claims 16 to 25, wherein the die is lubricated prior to use.
27. A process as claimed in any one of claims 16 to 26, wherein the die has a net shape of the required product.
28. A process according to the invention for producing titanium-magnesium alloy powders substantially as hereinbefore described or exemplified.
29. A method process of for producing titanium-magnesium alloy powders including any new and inventive integer or combination of integers, substantially as herein described.
30. A process according to the invention for producing a sintered product manufactured from a titanium-magnesium alloy powder substantially as hereinbefore described or exemplified.
31. A process of producing a sintered product manufactured from a titanium- magnesium alloy powder including any new and inventive integer or combination of integers, substantially as herein described.
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Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
ITMO20130084A1 (en) * 2013-03-29 2014-09-30 K4Sint S R L METAL MECHANICAL ALLOCATION PROCEDURE
CN104084591A (en) * 2014-07-03 2014-10-08 哈尔滨工业大学 Method for preparing Ag-Cu-Ti nano-alloy solder
CN105537799A (en) * 2015-12-24 2016-05-04 昆明贵金属研究所 Agcuti active brazing filler metal and preparation method thereof
WO2018125314A3 (en) * 2016-09-07 2018-09-13 Massachusetts Institute Of Technology Titanium-containing alloys and associated methods of manufacture
US10407757B2 (en) 2013-03-14 2019-09-10 Massachusetts Institute Of Technology Sintered nanocrystalline alloys
CN111266592A (en) * 2020-03-25 2020-06-12 燕山大学 Titanium-magnesium composite material with double-communication structure and preparation method and application thereof
CN111961917A (en) * 2020-08-25 2020-11-20 中国石油天然气集团有限公司 Graphene oxide reinforced titanium alloy and preparation method thereof
CN111996404A (en) * 2020-08-21 2020-11-27 中南大学 Titanium-based alloy with both quantitative magnesium loading and slow magnesium ion release functions and preparation method and application thereof
US11644288B2 (en) 2015-09-17 2023-05-09 Massachusetts Institute Of Technology Nanocrystalline alloy penetrators

Non-Patent Citations (3)

* Cited by examiner, † Cited by third party
Title
FUSHENG SUN, F.H. FROES: "synthesis and Characterization of Mechanical-alloyed Ti-xMg Alloys", JOURNAL OF ALLOYS AND COMPOUNDS, no. 340, 1 January 2002 (2002-01-01), pages 220 - 225, XP002638717 *
MACHIO C., NYABADZA D., CHIKWANDA H.K., PHASHA M.: "Mechanical Alloying and Sintering of Ti-10wt.% Mg Powders", MATERIALS SCIENCE FORUM, vol. 618-619, 1 January 2009 (2009-01-01), Switzerland, pages 105 - 108, XP002639365, Retrieved from the Internet <URL:http://www.scientific.net/MSF.618-619.105> [retrieved on 20110525] *
MUSHOVE T., CHIKWANDA H. MACHIO C, NDLOVU S: "Ti-Mg Alloy Powder Synthesis Via Mechanochemical Reduction of TiO2 By Elemental Magnesium", MATERIALS SCIENCE FORUM, vol. 618-619, 1 January 2009 (2009-01-01), Switzerland, pages 517 - 520, XP002639364, Retrieved from the Internet <URL:http://www.scientific.net/MSF.618-619.517> [retrieved on 20110525] *

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