Specialty Products To Fill Nickel Niches

What’s so special about nickel? “Nickel is a superb alloying element,” answers John Jones, Toronto-based general manager of Inco Special Products. “For example, 70% of nickel is used in the famous 18/8 stainless steel. High-nickel alloys are used in gas turbine blades in jet airplanes. Nickel adds something different-strength, toughness and corrosion-resistance.

“We are strong believers that nickel is a growth industry,” he says. There is a drive to expand the markets for all of Inco’s products, and the most aggressive marketing plan is in the Special Products area-powders, foam and coated fibres.

PROPRIETARY CARBONYL PROCESS

In 1889 Ludwig Mond discovered the nickel carbonyl refining process, and in 1902 the Mond Nickel Co. opened a nickel refinery in Clydach, Wales. That refinery and the proprietary carbonyl process was involved in the merger in 1929 of Mond Nickel and the International Nickel Co. of Canada (Inco’s predecessor). The carbonyl process is now the basis of nickel refining at Inco’s two refineries, the one at Clydach and the Copper Cliff refinery near Sudbury.

Process engineer Mary Dubel and packaging foreman Norm Desforges described for CMJ how the Copper Cliff refinery operates.

Put very simply, the granulated nickel matte arriving from the smelter enters the reactor where it reacts with carbon monoxide at high pressure (1,0000 psi or 68 atm) and relatively low temperature (156C) to form nickel carbonyl. The nickel carbonyl is purified in a distillation column, which results in liquid and vapour nickel carbonyl.

The physically interesting characteristic of nickel carbonyl is that it decomposes on heating into pure nickel metal and carbon monoxide off-gas. The hazardous aspect is that both nickel carbonyl and carbon monoxide are highly toxic, invisible gasses that have to be carefully handled.

The carbonyl gas is made into the bulk of the refinery products, nickel pellets used in nonferrous and special steel alloys and electroplating.

An interesting side of the business is the production of the Special Products (the powder and foam products) that are very pure, containing 99.97% Ni. The extremely pure nickel carbonyl can be made into a wide range of powders that vary in size, shape and surface characteristics to meet customers’ needs. The powders can be squashed together to form flakes, or grown into chains. The carbonyl gas can be used to coat carbon fibres. The Inco Technical Services research facility in Sheridan Park (Mississauga, Ont.) has been developing value-added products and finding new applications for existing products since 1992.

The powders have been in production at the Clydach refinery (which serves the European market) since 1944, and more recently at Copper Cliff. Copper Cliff has eight powder units that make a range of special powders for electroplating, nickel oxide and nickel salts (mainly). In 1982, Inco opened Novamet in Wyckoff, N.J., to specialize in small volumes and custom nickel powders, flakes and oxides.

The newer special product is nickel foam, which has been under development at Copper Cliff since 1992. The first INCOFOAM line began in 1994, and commercial production was achieved in 1996.

Rolls of dark grey polyurethane foam sheet slowly pass through a column containing nickel carbonyl vapour. The foam is slightly heated, so the nickel comes out of the carbonyl vapour to adhere to the surface of every pore in the foam, one atom at a time, forming an exact replica of the foam, in nickel. This process is much better controlled than electroplating, eliminating essentially all contaminants.

The plated foam then passes through an annealing furnace that uses a reduction process to burn off the polyurethane foam. The silvery grey annealed foam, now containing nothing but nickel, is carefully cooled so it retains all of the physical features of the initial foam. A non-destructive evaluation developed at Sheridan Park is done on every batch, checking the thickness, density, tensile strength and nickel content. The foam’s physical attributes-complete flexibility coupled with its incredibly large surface area and consistency from side to side and along its length-make it ideal for batteries and other special uses.

Copper Cliff still has the first commercial foam line, plating foam up to 36-cm wide. Using the same technology, the Clydach plant installed and commissioned a new foam plant last year with a scaled-up, one-metre-wide foam plater. A second line is now being completed there. The plant infrastructure is capable of making 1 million m2 per year of INCOFOAM.

PLANS TO DOUBLE SPECIAL PRODUCT SALES

In recent years Special Products have represented about 7-8% of Inco’s sales by weight and 12-13% by value, bringing in about US$200 million revenue per year. The company is targeting a doubling of this to US$400 within five years.

The reasons for this include Inco’s prediction that there will be continued growth in demand for certain products such as rechargeable batteries that need nickel powders and foam. Another reason is that the Special Products markets such as electronics and powder technology serve a different part of the economy than the traditional steel and alloys sector, with different business cycles. A shift toward this area would smooth out the fiscal bumps.

“One of the more exciting things is that nickel is coming back into the automotive areas,” says Jones. “Nickel use is coming back in powder metallurgy in low alloy steels for gears, and more importantly because of the coming in of hybrid and electric car batteries.”

Hybrid cars are powered by both a high-efficiency gasoline engine and a battery, but do not need external recharging of the battery. A reliable rechargeable battery is key to making hybrid and electric cars popular-a battery that can give a surge in power, can maintain a charge for a reasonable period, and can fit within the confines of today’s cars. Hybrid cars have already gained customer acceptance in Japan. Toyota and Honda are launching their hybrid vehicles commercially in North America and Europe this year, and the other auto-makers are watching the results carefully.

Nearly everyone who is working on electric or hybrid vehicles is working on a nickel battery, either nickel cadmium or nickel metal hydride. The batteries for these cars each typically contain 20 kilograms of nickel of various types. That’s a lot of nickel. Inco estimates that every one per cent of world vehicle production converted to hybrids similar to present designs, represents 10,000 tonnes of nickel per year.

Other sectors with major growth potential that will need nickel powders and foam include batteries for power tools and cellular phones, powder metallurgy parts, catalysts, and various electric uses. For all of these applications, Jones feels Inco has competitive advantages in its process economics and quality, research and development, and its customer positions.