Classifications

• • C—CHEMISTRY; METALLURGY
  • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
  • C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
  • C22B34/00—Obtaining refractory metals
  • C22B34/10—Obtaining titanium, zirconium or hafnium
  • C22B34/12—Obtaining titanium or titanium compounds from ores or scrap by metallurgical processing; preparation of titanium compounds from other titanium compounds see C01G23/00 - C01G23/08
  • C22B34/1236—Obtaining titanium or titanium compounds from ores or scrap by metallurgical processing; preparation of titanium compounds from other titanium compounds see C01G23/00 - C01G23/08 obtaining titanium or titanium compounds from ores or scrap by wet processes, e.g. by leaching
  • C22B34/1254—Obtaining titanium or titanium compounds from ores or scrap by metallurgical processing; preparation of titanium compounds from other titanium compounds see C01G23/00 - C01G23/08 obtaining titanium or titanium compounds from ores or scrap by wet processes, e.g. by leaching using basic solutions or liquors
• • 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
  • B22F9/16—Making metallic powder or suspensions thereof using chemical processes
• • C—CHEMISTRY; METALLURGY
  • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
  • C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
  • C22B34/00—Obtaining refractory metals
  • C22B34/10—Obtaining titanium, zirconium or hafnium
  • C22B34/12—Obtaining titanium or titanium compounds from ores or scrap by metallurgical processing; preparation of titanium compounds from other titanium compounds see C01G23/00 - C01G23/08
  • C22B34/1295—Refining, melting, remelting, working up of titanium

Definitions

• This invention relates to a process of making pulverulent metallic titanium from titanium-aluminum alloys.
• titanium-aluminum alloys for example by alumino-thermic reduction of titanium oxide, the aluminum being employed, for instance, in the form of shot.
• lime which forms with the nascent alumina a calcium aluminate slag protecting the metal during the reaction and the cooling.
• pulverulent metallic titanium is made by treating titanium-aluminum alloy, made by any desired process, with a reagent which attacks the aluminum but does not substantially attack the titanium.
• the reagent is an aqueous alkaline solution, a particularly suitable solution being an aqueous soda solution.
• Such solution attacks the aluminum, giving a sodium aluminate solution, but leaves the titanium substantially unaltered.
• a soda solution we may use a solution of sodium hydroxide, potassium carbonate or potassium hydroxide.
• the titanium-aluminum alloys which give the best results are those containing about 40 to 65% of titanium and about 60 to 35% of aluminum. However, compositions outside of these ranges can be employed but produce less desirable results. In any case, the composition of the alloy should be such that when treated with a reagent which attacks the aluminum it does not substantially attack the titanium.
• titanium-aluminum alloy it is particularly desirable to subject the titanium-aluminum alloy to a violent cooling from its molten condition as produced. This may be done, for example, by applying an abundant supply of water to it or by quenching it in water. Such violent cooling produces a structure in the solidified alloy which makes it easier to dissolve the aluminum from the alloy by means of an alkaline solution without substantially attacking the titanium. In addition, the violent cooling causes the solidified alloy to become brittle, which promotes its pulverization.
• the strength of the aqueous alkaline solution employed is not of great importance in the results obtained. However, other conditions being equal, the higher the concentration of the alkaline solution, the more rapid is the attack of the solution on the aluminum of the alloy.
• the process can be carried out in the following manner.
• a titanium-aluminum alloy is crushed, ground, and passed through a sieve of 1296 meshes per square centimeter. It can be passed through a sieve of 117 or 324 meshes per square centimeter, but the duration of the attack by the alkaline solution is considerably longer in such case.
• the shifted alloy is treated with an aqueous solution of soda at the boiling point of the solution (a little above 100 C.).
• the duration of the treatment until almost complete elimination of aluminum is accomplished varies according to the grain size of the powder and the concentration of the soda solution. For an alloy passed through a sieve of 829 meshes per square centimeter, for example, this time is about 8 hours for a soda solution nited States atent ii 2,750,271 Patented June 12, 1956 having a concentration of 6% by weight, and about 2 hours for a soda solution having a concentration of 10%.
• the titanium powder is filtered from the solution.
• the titanium powder usually contains a small amount of aluminum and an amount of oxygen, rather variable, usually within the range of 1 to 5%.
• This oxygen is in a hydrous form of titanium oxide, believed to be fixed on the surface of the titanium particles.
• Such oxide can be largely removed, according to the invention, by washing the titanium powder with a dilute acid, for example, hydrochloric acid, sulphuric acid, nitric acid, hydrofluoric acid, or a mixture thereof, at an acid concentration of a few hundredths per cent by weight.
• a dilute acid for example, hydrochloric acid, sulphuric acid, nitric acid, hydrofluoric acid, or a mixture thereof.
• Example 1 Titanium-aluminum alloy containing:
• the titanium powder after separating it from the solution, was deoxidized by washing it for 5 minutes in a sulphuric acid solution at a concentration of 5 by weight or in a mixture of equal parts of sulphuric acid having a concentration of 10% and hydrofluoric acid having a concentration of 1%. In each case the powder was washed with water after the acid washing. The proportion of oxygen was lowered in this manner to about 0.3%.

Landscapes

• Chemical & Material Sciences (AREA)
• Engineering & Computer Science (AREA)
• Geology (AREA)
• Life Sciences & Earth Sciences (AREA)
• General Life Sciences & Earth Sciences (AREA)
• Environmental & Geological Engineering (AREA)
• Manufacturing & Machinery (AREA)
• Materials Engineering (AREA)
• Mechanical Engineering (AREA)
• Metallurgy (AREA)
• Organic Chemistry (AREA)
• Chemical Kinetics & Catalysis (AREA)
• General Chemical & Material Sciences (AREA)
• Manufacture And Refinement Of Metals (AREA)
• Manufacture Of Metal Powder And Suspensions Thereof (AREA)

Applications Claiming Priority (1)

Publications (1)

Family

ID=8888823

Family Applications (1)

Country Status (5)

Cited By (11)

Families Citing this family (1)

Citations (2)

• 0
  • LU LU31972D patent/LU31972A1/xx unknown
  • BE BE517104D patent/BE517104A/xx unknown
• 1953
  • 1953-02-03 CH CH304809D patent/CH304809A/fr unknown
  • 1953-02-26 GB GB5457/53A patent/GB733712A/en not_active Expired
  • 1953-03-13 US US342286A patent/US2750271A/en not_active Expired - Lifetime

Patent Citations (2)

Also Published As

Similar Documents