Advanced Ceramics

Amongst the four elements that compose the modern Science and Engineering of the Materials - Composition and Structure, Synthesis and Processing, Properties and Performance -, the Synthesis and Processing are the basic element for the production of new materials with new properties and performance, as well as of products of high quality and low cost, being, therefore, determinative a crucial one of industrial productivity and, consequently, of the international competitiveness.

Kept the had ratios when compared with the developed countries, Brazil possess a reasonable scientific and technological base in the field of the science and eEngineering of materials and in areas correlated. However in the function of the absence of actions previously planned and articulated programs involving the Universities, Centers of Research and Industry, the activities of P&D, in its majority, has restricted to the elements structure and composition and properties, if not closing all the cycle of development of the materials. The synergy between the technological development, economic necessities and ambient factors comes causing a great change in the use of materials. This change is in the direction of if substituting traditional materials of the industry, mainly the metals, for that they have a better performance to a lesser cost. The material candidates for this substitution are plastic, ceramic, and its composites. Amongst the structural materials, the special ceramics (Si3N4, SiC, AlÒ3, ZrO2) are the greater of the challenges, therefore its fragile nature and statistics of behavior introduce one high complexity in the designs and the development of these materials.

The fields of application of specials ceramics even so, in general, the ceramic products special are of reduced dimensions, consist, in the majority of the times, basic components for the equipment of high technology. For this ratio they generate a considerable multiplying effect in the economy, presenting an index of leverage estimated of 11 for 1. This means that for each applied monetary unit to the ceramic products special, it makes possible or it exerts fort influence in an upper market of products 11 times.

In function of the intrinsic features of the ceramic materials, as low density, low thermal conductivity, high resistance to the corrosion and the abrasion and the capacity to support high temperatures without if deforming, beyond other specific features gifts in some these materials (super conductivity, ionic conductivity, nuclear properties, etc.), the use of these materials have grown of surprising form in a infinity of applications in the most diverse areas of the human knowledge, as shown in Figure 1, presented to follow. This growth is fruit of the advances of the scientific and technological knowledge in the field of the science and engineering of the materials occurred in the last decades. The applications in the field of the energy deserve special prominence, as fuels for nuclear reactors, the elements moderators and the materials for reactors the fusing, the components of automotivos engines - that they magnify the income and they propitiate the less noble fuel use -, vanes of turbines, dental brackets and implantations, tools for cut of high speed, materials of high resistance to the abrasion, as the guide wires in the industry of weaving, refractory special, electro-electronic components and, still, in products of popular consumption as knives and shears.

Despite these difficulties, this family of materials has had considerable advances in diverse fields of engineering, being able itself to cite that, for example, its application in automotive engines and diesel, turbines the gas, stamps of bombs, tools of cut, abrasives, membranes, biomateriais, and refractory comes gaining strong consideration and expansion in the market. Clear examples of this trend are presented by the Toyota, that come searching material ceramic for applications in high temperatures since the ends of the decade of 60 and developing processes of manufacture of ceramic components for automotive engines since 1979, and by the designers of gas turbines, that they wait to do a economy of generated electric energy of USS 500.000,00/ano/100MW with the ceramic use in the hot part of the turbines.

Processes and Technologies of Manufacture

The properties of special ceramics, as well as of the excessively material ones, basically are influenced by the quality of the raw materials from which the same ones are manufactured and by the final microstructure. Thus being, any attempt of control of the properties of a product must pass for the agreement of the basic properties of the materials, as well as for the manufacture process during which the final microstructure if develops.

The classified products as being special ceramics are elaborated, in its great majority, from raw materials that need a rigorous control, as much in the process of attainment of the powders, to guarantee important characteristics (pureness and particle size), how much during the conformation and thermal handling of these raw materials in parts and end items (sintering). The materials are elaborated aiming at the attainment of properties that take care of the specific uses.

The success and the commercialization of special ceramics of high performance depend basically on two factors: the quality and low cost of the raw materials (powders, additives, etc.) e the perfectioning of the processing methods. The capacity of if finding forms efficient of production of resistant materials, especially of complex forms and with thick sections, it is essential to take care of to the demand the market and the diversity of demanded products.

World-wide market and Applications of Ceramics Special

Japan and United States are the two bigger special ceramics markets, with respective values of USS 7,71 Billion and USS 5.53 Billion, in 1995. The situation of the Europe is more modest, with national markets adding approximately USS 1.5 Billion. It is not made use of necessary data on the markets of other countries, beyond Japan and the United States, what it makes it difficult particularly the description of the world-wide panorama as a whole. In any way, he is well-known that these two countries today lead the production and the consumption of special ceramics, and are probable that this leadership continues in the future.

The special ceramics industry in U.S.A. has 450 companies approximately. This market, that includes structural ceramics, eletronic ceramic, products for the environment (catalytic, substracts, membranes, etc.) and coverings, is estimated in USS 8.7 Billion for year 2000, with a tax of growth, foreseen, of 9.5% to the year. Similar taxes of growth are waited for the Japanese and European market, estimating for 2000 year USS 12.2 Billion and USS 2.36 Billion, respectively. Thus, the world-wide market in year 2000, will have to reach USS 24 Billion approximately.

In the field of the ceramic specials materials for structural ends, there is a expressive market that will have approximately to put into motion USS 2.1 Billion in 2000, mainly in applications come back to the resistance to the consuming, ceramic membranes, tools of cut, components to engines, exchangers of heat, biomedical, aerospace and of defense components, super refractory abrasives and of raised performance, where of the cited applications, orderly use decreasing, the components directed to applications that require high resistance to the abrasion, refractory of raised performance, membranes and cut tools answer approximately for 80% of the market. Of these four, the resistant components to the abrasion and the refractory ones of raised performance answer for about 60% the demand.

Market in Brazil

In Brazil, the available data necessary and/or are not outdated, but a significant growth of the national market for the classified ceramic products is observed as special, following the verified trend the world-wide level. Study carried through for the ABPTI 1988 indicated for the Brazilian market of ceramic products special in values of about USS 250 million.

Being overcome as base the tax of annual growth of signaled 9.5% for the world-wide market, could be estimated that in the end of the present decade the national market would correspond about USS 743 Million. However, admitting that this market has similar evolution to the European and that in 2000 its size is proportional to the ratio enters the PIBs of the Europe and Brazil, it is possible to estimate, from the expectation of the European market for specials ceramics (2.36 Billion) that the national market comes if to point out around USS 200 Million in 2000, what it seems to be a more trustworthy number and conservative to survey it potentiality of the market.