ПРОГРЕССИВНЫЕ ТЕХНОЛОГИИ В МАШИНОСТРОЕНИИ THE ADVANCED TECHNOLOGIES IN MECHANICAL ENGINEERING E. Błachowicz, Z. Kopacz SOME PROBLEMS OF CHEMICAL TREATMENT OF MAGNESIUM ALLOYS APPLIED IN THE AUTOMOTIVE INDUSTRY In the last years the considerable increase of the use of magnesium alloys is noted, especially in the automotive industry. <...> The driver of this increase is the possibility of the weight reduction of car for decreasing of fuel consumption and next the achieve of economic and ecological effects. <...> Together with the increase of use of magnesium alloys the development of investigations of new production technologies of magnesium itself and its alloys - which will have, among others, better corrosion resistance - is noted. <...> Regarding on, among others, the weak anticorrosive properties, the preparation of surface of magnesium alloys, treated as a final processing, or as the processing previous further technologies, especially coatings, state the particularly important problem. <...> Turn attention onto fact, that many modern technologies - recommended to chemical processing of magnesium alloys, were successfully tried out on aluminium alloys In the paper the different possibilities of magnesium application in automotive as well as chemical surface treatment of magnesium were described. <...> KEY WORDS: magnesium, automotive application, chemical surface treatment metals (density1,74 g/cm3) – one third lighter than aluminum. <...> Tide and dense layer of magnesium oxides protects the surface of metal against the corrosion in the air. <...> Above advantages and 100% recycle-ability gives to magnesium the position of the best material for many application including automotive, aerospace, electronics, medicine and sport. application in the production of ultra-light alloys (density about 1,8 g/cm3) together with Magnesium in metallic form has found its such alloying elements as: aluminum (2,5–10%), zinc (0,2–5%), manganese (0,1–0.5%), zirconium (0,4– 1,1%), and rare-earth elements (0,15 – 4%). <...> We can distinguish two technological groups of alloys: I – casting magnesium alloys, characterized by good castability, tightness (resistance penetration of liquid and gas) onto and good machineability II – magnesium alloys for metalforming, with good mechanical properties and good weldability. <...> Polish Standards [1,2] parts of aircrafts and and technological guidebooks [3] describe many of various grades of magnesium alloys and magnesium itself, designated for big number of applications. <...> In each of them, very good <...>