Abstract: A process is described for producing a superconducting thick layer on a base material by thermally spraying a powder containing bismuth, lead, strontium, calcium and copper in oxidic form. First a powdered starting mixture is prepared which has a composition corresponding to the formula:Bi.sub.1.90-x Pb.sub.x Sr.sub.2-y Ca.sub.2.2-z Cu.sub.3.5-q O.sub.v,in which0.1.ltoreq.x.ltoreq.0.7,0.ltoreq.y.ltoreq.0.4,-0.5.ltoreq.z.ltoreq.+0.5,0.ltoreq.q.ltoreq.1.2 andv is the oxygen content calculated from the starting materials. Then the powder is heated for not less than 1 hour at a temperature of not less than 750.degree. C. in an oxygen-containing atmosphere and cooled again. The powder pre-reacted in this way is applied to a thermally stable substrate in a layer thickness of 0.5 to 7 mm by means of a burner by plasma-jet spraying or by flame spraying. The layer applied is then sintered for a time of not less than 40 hours at a temperature of 842.degree. to 848.degree. C. The layer is cooled to a temperature of 550.