Surface Phenomena: A Cornerstone of Iron and Steelmaking Processes.

Mr. Masao YUKAWA was a very prominent per- sonality of the Japanese lron and Steel Industry.Thisyear, on his 90th birthday.I am pleased to contribute to acknowledge the very important part he played in the spectacular development of lron and SteelTechnologyin Japan, which was also taken as a lesson in many industrial countries in the world.As a good example of his spirit of international cooperation, it is worthwhile to mention his participa- tion in the construction of the USIMlNAS steel plant in lpatinga, Brazil, which I had the opportunity to visit and to see in successful operation someyears ago.It is, for me, a great honour to have been invited to join, in 1993, the very impressive list of distinguished YUKAWA Memorial Lecturers.As Masao YUKAWA had a very wide perspective of lron and Steelmaking Processes.I will try to day, in memory of him, to show the importance of Surface Phenomena, a real "cornerstone", in pyrometallurgical processes involved in steel production.1.