EXHIBIT 21 Subsidiaries of Registrant The Company has the following subsidiaries, all of which are wholly owned and included in the consolidated financial statements. State or Country Name of Subsidiary of Incorporation - ------------------ ---------------- BEM Services, Inc. Ohio Brush Ceramic Products Inc. Arizona Brush Wellman Inc. Ohio Brush International, Inc. Ohio Brush Resources Inc. Utah Brush Wellman GmbH Germany Brush Wellman (Japan), Ltd. Japan Brush Wellman Limited England Brush Wellman (Singapore) Pte Ltd. Singapore CERAC incorporated Wisconsin Circuits Processing Technology, Inc. California OMC Scientific Holding Limited Ireland Technical Materials, Inc. Ohio Thin Film Technology, Inc. California Williams Advanced Materials Inc. New York Williams Advanced Materials Pte Ltd. Singapore Williams Advanced Materials (Netherlands) B.V. Netherlands Zentrix Technologies Inc. Arizona