Recently,relying on the self-developed 3150kW cold cathode electron beam cold hearth furnace (EB furnace)by its subsidiary Baoti Equipment Technology Co., Ltd.Baoti Gropu has successfully smelted and and produced 12-ton ultra -large single-weight pure nickel ingots and realized stable mass production.
It represents a major leap forward in domestic EB furnace smelting processes and manufacturing technology for large-tonnage high-end nickel ingots, further strengthening the independent supply capacity of high-end equipment materials and driving the high-quality development of the special new material industry.
Pure nickel features outstanding resistance to strong acid and alkali corrosion, high-temperature oxidation and stress corrosion. It is an indispensable strategic core material for demanding working conditions such as chlor-alkali new energy, seawater desalination, high-end fine chemical engineering and deep-sea marine engineering. Nevertheless, pure nickel smelting is highly challenging. Under high-temperature and high-vacuum conditions, nickel is prone to volatilization loss. Molten nickel boasts high viscosity and poor fluidity, which easily leads to quality issues including uneven molten pool temperature, component segregation, surface oxidation and internal defects during production. It imposes stringent requirements on the vacuum tightness of smelting equipment, precise temperature control of electron beams and the stability of long-term continuous operation. Stable mass production of large-tonnage pure nickel ingots has long been a key bottleneck restricting industrial development.
Following the non-ferrous metal collaborative development strategy of Shaanxi Nonferrous Metals Group, Baoti Group targets the goal of independent controllability of high-end special materials and carries out concentrated technical research. In December 2023, the cold cathode electron beam cold hearth furnace independently developed by Baoti Equipment was put into operation, replacing the original imported equipment from Germany. The domestic cold-gun EB furnace overcomes the technical shortcomings of traditional hot cathode EB furnaces in nickel ingot smelting, expands the range of smeltable materials and opens up a brand-new technical path for the industrialization of nickel ingots.
Since there are no mature processes or directly referable parameters in China, the whole technical system has to be explored from scratch. In March 2025, Baoti Group officially launched a special research project for large-tonnage pure nickel ingots and set up a dedicated R&D team. At the initial trial production stage, the project encountered repeated difficulties including unstable working conditions, mismatched parameters and fluctuating product quality. Centering on pain points such as material adaptation, process control and steady-state smelting, the team conducted repeated verification and iteration, eliminated hidden troubles one by one and optimized process parameters to form a complete chain for the development and large-scale production of high-purity large-tonnage nickel ingots.
To ensure smooth project delivery, the team built a full-dimensional quality and safety guarantee system covering manpower, equipment, materials, methods and environment. To tackle the bottleneck of recycled material feeding, special packaging devices were independently designed to form standardized feeding processes and ensure continuous and stable material supply. Before production, the smelting equipment was carefully cleaned to strictly control impurity contamination risks. Core components such as cold cathode electron guns, cooling systems and scanning coils were calibrated and inspected precisely to avoid overheating and unplanned shutdown risks. Meanwhile, on-the-job practical training was organized to unify smelting specifications and abnormal condition handling procedures.
During smelting, with the support of an intelligent online monitoring system, the team monitored molten pool status, electron beam trajectory, furnace vacuum degree, smelting speed and other working data in real time, realizing visualized, controllable and precise regulation of the whole smelting process. To address stubborn technical problems caused by poor fluidity of molten nickel, such as cold shut defects, temperature imbalance and electron gun power fluctuation, the team kept optimizing key parameters including electron beam scanning pattern, output power and smelting rate. Through multiple rounds of steady-state smelting review and iteration, the core difficulties in smelting large-tonnage pure nickel ingots were overcome. The finished 12-ton ultra-large single-weight pure nickel ingots feature dense internal structure and uniform chemical composition with excellent overall quality, realizing continuous, standardized and large-scale mass production of this specification.
The mass production of large-tonnage pure nickel ingots is an important milestone for Baoti Group to boost domestic substitution of key materials and pursue technological self-reliance. It is also a successful practice of extending and transforming titanium smelting technology into the nickel material sector. It fully verifies the comprehensive capabilities of the group in equipment development, process R&D and on-site collaborative support. Going forward, Baoti Group will continue to deepen its layout in the rare metal new material industry, accelerate the development into a world-class leading enterprise, guarantee the independent and controllable supply of high-end special materials, and contribute to the high-quality development of China's new material industry.
(Source: China Nonferrous Metals Magazine)
(The above content is compiled from online sources and for sharing purposes only)
