Prof. Dr. Stephan Wolynec is full professor (emeritus) at the Department of Metallurgical and Materials Engineering of the Escola Politécnica da USP. He is one of the most important brazilian researchers in the field of metallic corrosion and was deeply involved with the PROALCOOL project since the begining. I invited him for an interview and he, graciously, accepted. The content of this interview follows...
(Noted added for the help of the reader: Telex is an ancient communication medium, found today only in Technology Museums around the world - it was the poor equivalent of an e-mail twenty to thirty years ago).
CGS: Please review the role of the university and of the research centers in the PROALCOOL project.
SW: The use of ethanol as a substitute of gasoline in cars in Brazil was motivated by the petroleum crisis started in 1973, which was aggravated in the last years of that decade. To overcome this situation, the Brazilian government launched the “Proalcool” program, through which it stimulated the car manufacturers to develop an ethanol fuel powered car.
The response of car manufacturers was positive, and their initial concern was basically directed, as expected, to optimize the parameters responsible for the engine performance. It was believed that it was sufficient to replace the engine of the gasoline powered car by the new engine to obtain the ethanol fuel powered car. However, it was soon realized that the ethanol fuel was not compatible with most of the materials used in the gasoline car due to corrosion problems, and that the undertaking of new materials selection was mandatory.
Two manufacturers (Fiat and Volkswagen), after adopting some surface treatments in some components of the gasoline car, started the production of ethanol fuel powered cars in the beginning of the 80’s. A euphoric start of a new automotive transport era was witnessed, which gradually began to fade due to the technical shortcomings of the new vehicle, which had in corrosion its implacable enemy. The complaints of bad performance of the vehicle, difficulties in starting the engine in cold days, the high fuel consumption, were growing, and the sales of these vehicles were collapsing. It seemed that the ethanol car had no chances to compete with its older brother, the gasoline car. However, in August of 1980 the government summoned a meeting between the car manufactures, universities and research institutes in order to discuss the possibilities of a collaborative work to solve the corrosion problems in ethanol fuel powered cars. The response of the participants of that meeting was highly positive, and the collaborative work started almost immediately. As a consequence, in the end of 1981 the ethanol fuel powered cars were already representing more than 50% of new cars in the automobile market. The participation of research institutes and university was decisive in the solution of corrosion problems. The new ethanol car became, in terms of performance and fuel consumption as good, or even better, than the gasoline car.
CGS: Which part did you play in this?
SW: At that time I was head of the Corrosion and Electroplating Laboratory at the Technological Research Institute of the State of São Paulo (IPT). This laboratory became heavily involved in the study of corrosion and corrosion protection against ethanol fuel. We performed decisive works initially with Ford and afterwards with Volkswagen. More than 10 papers were published and a considerable amount of technical reports were issued for different manufacturers involved in the task of solving the corrosion problems in ethanol cars.
CGS: The introduction of ethanol as an automobile fuel lead to considerable corrosion related difficulties at the time. Could you please explain this to our audience?
SW: The corrosion problems in the ethanol car were observed in many components. However, the most critical was that of the carburetor. At that time the carburetors in Brazil were essentially made of Zamak alloy (zinc-aluminum-copper alloy), and only in some few cars aluminum alloy carburetors were used. Already during the development stage it was found that Zamak and aluminum alloy were not corrosion resistant to ethanol and that some protective coating was necessary. Thus, the first attempt was to apply to Zamak carburetors a double dip chromate coating, but it was soon realized that the improvement in corrosion resistance it provided was only temporary.
In the first ethanol cars the corrosion of the carburetor, which is a vital component of a vehicle, was responsible for a considerable amount of corrosion products, which were dragged by the fuel, obstructing the calibrated orifices and interfering with the normal flux of the fuel, causing frequent problems of engine adjustment and increasing the ethanol consumption.
It can be stated that the ethanol car became viable only after the corrosion problems of the carburetor were solved. This was achieved when the Zamak carburetors became plated with electroless nickel. The idea of using this type of coating come out in a meeting at IPT that I and my colleagues from the Corrosion and Electroplating Laboratory had with the people of Ford R&D Laboratory. The Ford car manufacturer was the first to produce ethanol cars with this type of carburetor.
Coatings of other components of the car had also to be substituted for new coatings resistant to ethanol fuel. Thus, in the fuel tank the lead/tin coating (terne plate) was substituted by a tin coating with an intermediary coating of copper. All zinc coated components, chromatized or not, were substituted by cadmium chromatized components.
The ethanol car, in terms of materials used in its manufacture, became significantly different from the gasoline car. More than 300 components in the ethanol car are different from those used in gasoline car.
CGS: The recent introduction of the bi-fuel engines (the so called FLEX technologies), in my opinion, was quite smooth, in the meaning the the whole development, from the idea to the production, was made in a couple of years. Does this means that the above mentioned corrosion issues have been solved?
SW: I am not acquainted with this development. But, the development of the ethanol car had a very satisfactory effect upon the Brazilian car manufacturers. Before this development, we used to joke that their R&D laboratory was the telex. Every time they had a technical problem, they sent a telex to the parent firm in Unites States or Germany, and got the answer on how to solve it. But this did not work with the ethanol car. The development of this car forced the Brazilian car manufacturers to invest in their own R&D capabilities. Thus, I believe that presently they have highly qualified people and facilities to undertake the development of such technologies as the FLEX bi-fuel engines. Moreover, with the development of the ethanol car I am sure they learned how to solve the corrosion problems.
CGS: What are the actual research challenges in corrosion in ethanol media?
SW: Up to now the corrosion mechanism in ethanol media has not been properly established. This is a scientific challenge, but if we learn about this mechanism, new methods of corrosion protection could be discovered, both more efficient and cheaper.
CGS: Was the Proalcool project a successful example of interaction between universities, research centers and industries? Have we learned something from this experience?
SW: It certainly was. We had a big challenge to develop a new type of car, powered by ethanol fuel. In no place in the world there was a ready answer for this challenge. The Proalcool program showed that by joining efforts of industry engineers with that of university and research institutes scientists it was possible to develop, without relying on imported technology, and in a relatively short time, a Brazilian know-how. From this experience we learned that the scientific and technological expertise of our universities and research institutes can efficiently support the innovation efforts of our industries.