Risk aversion plunged on the positive news of the Russia-Ukraine talks. After several days of rising oil prices, the price of precious metals continued to fall. Domestic futures markets remain stable for the time being.
Back in international markets, WTI crude futures briefly dipped below $100 a barrel, while Brent crude hit its lowest intraday level in nearly two weeks. Spot gold briefly fell below $1,900 an ounce. Comex gold futures closed down 1.1 percent at $1,918.4 an ounce. Comex silver futures closed down 1.14 percent at $24.91 an ounce. "Recently, crude oil prices have been extremely sensitive to changes in geopolitical news." Traders believe that the current oil price is still in the broad impact, Ukraine will still be a premium in the case, although the market further decline, but should not be too pessimistic, it is recommended to wait and see for the time being. The Ukrainian premium is still there and there will be some volatility in the nickel titanium alloy market.
Introduction to Nickel Titanium Alloy Powder
Nickel-titanium alloy or nitinol is a binary alloy composed of nickel and titanium, which is a shape memory alloy. The shape memory alloy is a special alloy that can automatically restore its plastic deformation to its original shape at a certain temperature. Its expansion rate is more than 20%. The fatigue life is 1*10^7. The damping characteristics are 10 times higher than ordinary spring. Its corrosion resistance is better than the best medical stainless steel, so it can meet all kinds of engineering and medical application needs, is a very good functional material.
In addition to the unique shape memory function, memory alloy also has excellent characteristics such as wear resistance, corrosion resistance, high damping, and superelasticity.
Nitinol alloy has two different crystal structure phases due to the change in temperature and mechanical pressure, namely the austenite phase and martensite phase. The phase transition sequence of Nitinol during cooling is the parent phase (austenite phase) -R phase - martensite phase. The R phase is rhomboid, the austenite is at a higher temperature (greater than the same: the temperature at which austenite starts), or when the load is removed, cube, hard. The shape is relatively stable. While the martensite phase is relatively low temperature (less than Mf: the end of martensite temperature) or loading (by external activation) state, hexagonal, ductile, repetitive, unstable, easy to deformation.
Physicochemical Properties of Nickel-Titanium Alloy Powder
1)Shape memory. Shape memory is that when the parent phase of a certain shape is cooled from above Af temperature to below Mf temperature to form martensite, the martensite is deformed at below Mf temperature and heated to below Af temperature. With the reverse phase transformation, the material will automatically restore its shape at the parent phase. In fact, the shape memory effect is a thermally induced phase transition in Nitinol.
2) Superelasticity. The so-called superelasticity refers to the phenomenon that a specimen has a strain far greater than its elastic limit under the action of external forces, and the strain can be recovered automatically during unloading. That is, in the parent state, due to the action of applied stress, the stress-induced martensitic transformation occurs, and the alloy exhibits mechanical behavior different from that of ordinary materials. Its elastic limit is far greater than that of ordinary materials, and it no longer obeys Hooke's law. In contrast to shape memory properties, superelasticity has no thermal involvement. In a word, hyperelasticity means that the stress does not increase with the increase of strain in a certain range of deformation. Hyperelasticity can be divided into linear hyperelasticity and nonlinear hyperelasticity. In the former stress-strain curve, the relationship between stress and strain is nearly linear. Nonlinear hyperelasticity refers to the results of stress-induced martensitic transformation and its inverse transformation occurring during loading and unloading processes within a certain temperature range above Af, so nonlinear hyperelasticity is also called phase transformation pseudo-elasticity. The pseudo-elasticity of Nitinol alloy is about 8%. The superelasticity of Nitinol alloy can be changed with the change in heat treatment conditions. When the bow wire is heated to 400C or above, the superelasticity begins to decrease.
3)Sensitivity to oral temperature. Stainless steel wire and CoCr alloy tooth orthotic wire orthotic force is basically not affected by oral temperature. The orthodontic force of superelastic Nitinol orthodontic wire varies with the change in oral temperature. When the amount of deformation is constant. As the temperature rises, the orthodontic force increases. On the one hand, it can accelerate the movement of teeth, because the temperature change in the oral cavity will stimulate the blood flow in the area of blood stagnation caused by the capillary stagnation caused by the appliance so that the repair cells in the process of tooth movement can be fully nourished, and maintain their vitality and normal function. Orthodontists, on the other hand, cannot accurately control or measure corrective forces in the oral environment.
4)Corrosion resistance. Research shows the corrosion resistance of nickel-titanium wire is similar to that of stainless steel wire.
5)Toxicity resistance: Nickel-titanium shape memory alloy contains about 50% nickel, which is known to have carcinogenic and cancer-promoting effects. In general, the surface layer titanium oxidation acts as a barrier, making the Ni-Ti alloy have good biocompatibility. TiXOy and TixNiOy of the surface layer can inhibit Ni release.
6)Soft orthodontic force. Commercially applied dental orthodontic wires include austenitic stainless steel wire, cobalt-chrome-nickel alloy wire, nickel-chromium alloy wire, Australian alloy wire, gold alloy wire, and ß titanium alloy wire. Load-displacement curves of these orthodontic wires under tensile test and three-point bending test conditions. The unloading curve platform of Nitinol is the lowest and the flattest, indicating that Nitinol can provide the most durable and gentle correction force.
7)Good shock absorption. The greater the vibration caused by chewing and night molars on the archwire, the greater the damage to the root and periodontal tissue. Through different attenuation experiment results, the study found the archwire stainless steel wire vibration amplitude is larger than hyperelastic nickel-titanium silk, super-elastic nickel-titanium archwire the initial vibration amplitude is only half of stainless steel wire, good vibration and shock absorption characteristics of the archwire is important for the health of the teeth, and traditional archwire such as stainless steel wire, tend to increase the root absorption.
|Nickel Titanium Alloy Powder Properties|
|Other Names||nickel-titanium, shape-memory nitinol, NiTi, Ni-Ti|
|Solubility in H2O||N/A|
Applications of Nickel-Titanium Alloy Powder
Ni-Ti alloy is widely used in the fields of biological medicine, aerospace, national defense, and military industry.
Main Supplier of Nickel-Titanium Alloy Powder
Luoyang Tongrun Nano Technology Co. Ltd. (TRUNNANO) is a trusted global chemical material supplier & manufacturer with over 12-year-experience in providing super high-quality chemicals and Nanomaterials, including metal alloy, nitride powder, graphite powder, zinc sulfide, calcium nitride, 3D printing powder, etc.
If you are looking for high-quality Nickel Titanium Alloy Powder, please feel free to contact us and send an inquiry. ([email protected])
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