Nb-1Zr alloy Crucible

Nb-1Zr alloy crucible used in the experiment is made of Nb-1Zr (R04251) refractory alloy material. It is mainly used for high-temperature experimental development in universities, research institutes, and material laboratories.

By adding 0.8-1.2% of zirconium to the metallic niobium matrix, grain refinement is achieved. Compared to pure niobium crucibles, its high-temperature creep resistance and thermal shock resistance have significantly improved. The melting point is approximately 2400℃, and the high-temperature vapor pressure is low, making it less prone to impurity precipitation and contamination of the experimental samples.

Nb-1Zr alloy Crucible product parameters

	Nb-1Zr alloy Crucible
	Nb-1Zr
	Nb: Balance; Zr:0.8~1.2; O<=0.025; C<=0.01; N<=0.01; H<=0.0015; Impurities: Ta,Fe,Si,W etc.

1. Selection of Nb-1Zr alloy crucible raw materials :

The Nb-1Zr ingot used is produced by VAR vacuum self-dissolution melting process. The interstitial elements O/H/N are strictly controlled, and there are no inclusions, porosity, or segregation. The alloy rod or plate with low oxygen and high purity Nb-1Zr is preferred.

Note: The raw materials must not contain high-melting-point impurities such as tungsten and iron. If these high-melting-point impurities are present, they will contaminate the experimental samples at high temperatures.

2.The forming of the niobium-zirconium alloy crucible is mainly achieved through spinning molding and CNC precision machining. Here, we do not recommend simple forging rough processing.

Because the spinning molding process can ensure uniform wall thickness of the crucible, avoiding local wall thickness differences that cause local overheating and stress concentration; Machining can better ensure the small tolerance of inner diameter, outer diameter, height, and bottom thickness, and the bottom of the crucible is flat, stable for placement, and particularly suitable for laboratory small furnace bodies.

For irregular / conical crucibles that need to be formed as a whole, the welding process should be minimized as much as possible. If welding is necessary, vacuum electron beam welding should be adopted, and argon arc welding is prohibited. This can ensure that the weld composition, grain structure, and base material are consistent, and the weld has no pores or cracks. Otherwise, the crucible is particularly prone to high-temperature leakage during the experimental use.

3. Heat treatment

After the crucible is formed, vacuum stress relief annealing is required to eliminate the residual stress from spinning / machining. This is mainly to prevent the crucible from cracking or deforming under the thermal shock of heating and cooling during the experiment, thereby stabilizing the grain structure and improving the thermal shock resistance.

4. Cleaning and degassing process:

• Vacuum high-temperature degassing treatment, which is mainly used for high-demand research crucibles. The internal H₂O, H₂, CO and other gases adsorbed by the material need to be released in advance

This is mainly to prevent the crucible from releasing gas during the experimental heating, avoiding sample contamination by gas and bubble formation in the melt, which is the most concerned point for laboratory customers.

For Laboratory High-Temperature Melting, Sintering And Thermal Analysis, The Main Applicable Metal Materials Are As Follows:

Alkali metals, mainly liquid lithium Li, sodium Na, potassium K. The Nb-1Zr crucible has excellent corrosion resistance for molten alkali metals and is the preferred experimental container for liquid alkali metal experiments in the space / nuclear field. There is almost no interdiffusion and no brittle intermetallic compounds are produced.

Precious metals, mainly gold Au, silver Ag, platinum Pt, palladium Pd, rhodium Rh. They have excellent compatibility at high temperatures and do not easily undergo element intermixing, and are very suitable for precious metal sample melting and purification experiments.

Rare earth metals and rare earth alloys, such as lanthanum, cerium, neodymium, samarium, dysprosium and other rare earth metals, rare earth intermediate alloys (mainly due to the use in a vacuum environment and reasonable temperature control).

Refractory metals (low reaction system, medium-low temperature range), mainly tungsten W, molybdenum Mo sample sintering or annealing experiments; Please note that if the temperature is too high and the holding time is long, there is a risk of trace element interdiffusion.

Uranium, plutonium type nuclear metals (research nuclear material laboratory), have good compatibility with molten uranium metal, and are commonly used crucibles for early liquid metal nuclear experiments.

Copper Cu: Medium-temperature vacuum melting of copper and copper alloys. It should be noted that during the operation, the temperature should not exceed 1200℃ for a long time. At high temperatures, there will be a small amount of corrosion.

Also suitable for metal powder sintering, heat treatment, not limited to melting, many laboratories use it for high-temperature annealing of alloy powders.