Ni-Hard Casting Manufacturer

Koje su tipične primjene Ni-Hard odljevci u industriji rudarstva, betona i šljunka?

1. Mining Crushing and Grinding Equipment: Due to its high hardness and wear resistance, Ni-Hard castings are widely used in key components such as ball mill liners, hydraulic breakers, grinding rollers, and conveying pipelines, maintaining a long service life during high-load ore crushing and grinding processes.

2. Concrete Mixing and Conveying Systems: In concrete mixers, conveying screws, and pump casings, Ni-Hard castings can withstand the strong impact and abrasion of concrete particles, improving equipment reliability and maintenance intervals.

3. Gravel Conveying and Sandblasting Equipment: Used in gravel conveying pipelines, sandblasting nozzles, and blower blades, Ni-Hard's high hardness and impact resistance ensure that it is not easily worn or deformed in high-speed, sand-containing media environments.

4. Other High-Abrasion Applications: Ni-Hard castings can be used in applications such as mining screens, slag conveying pumps, and steel rolling mill rolls to provide dual protection against wear and impact.

Kako se Ni-Hard odljevci ponašaju u visokotemperaturnim i vlažnim okruženjima?

1. Otpornost na oksidaciju pri visokim temperaturama: Ni-tvrde legure sadrže približno 1,4–2,5% kroma i 3,4–4,75% nikla. These two elements form a dense oxide film on the surface at operating temperatures of 300–400°C, significantly enhancing oxidation resistance.

2. Corrosion Resistance in Humid Environments: Studies show that Ni-Hard castings maintain good corrosion resistance in humid or water-vapor-containing environments, mainly due to the protective oxide layer formed by chromium and the passivation effect of nickel. To rezultira mnogo nižom stopom gubitka mase pri visokim temperaturama, vlažnim uvjetima u usporedbi s običnim bijelim lijevanim željezom s visokim sadržajem kroma.

3. Učinak toplinske obrade na koroziju: Kaljenje na visokoj temperaturi ili popuštanje može prilagoditi udio zadržanog austenita u matrici. A moderate amount of retained austenite helps form a fine martensite-austenite mixed structure on the working surface, further improving resistance to crack propagation and corrosion cracking.

4. Practical Application Verification: In field applications of ball mill liners and gravel conveying pipelines in mines, Ni-Hard castings exhibited extremely low corrosion rates and stable mechanical properties under long-term high-temperature and humid working environments, verifying their excellent corrosion resistance.