In this paper the current knowledge about the influence of alloy additions used in galvanizing baths has been analysed. The optimum concentration of Al, Ni and Pb addition has been established. Tests have been conducted to determine the synergistic influence of the addition of AlNiPb in a zinc bath upon the structure and growth kinetics of coatings. The structure and the chemical composition of coatings obtained on steel with low silicon contents and on Sandelin steel have been developed. It has been determined that the synergistic influence of the AlNiPb addition effectively lowers the reactivity of Sandelin steel and it improves zincs flowing off the product surface which results in decreased zinc consumption and better appearance of the coating. The structure of coatings obtained in a Zn-AlNiPb bath on Sandelin steel is similar to the structure of coatings obtained on low-silicon steel.

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The article presents investigation of steel subjected to external stress during hot-dip metallization. The results of experimental investigations of the LME phenomenon, reasons of its formation and influence of different parameters are described. Samples made of C70D steel subjected to various loads inducing tensile stress (400-800 MPa) during hot dip metallization ina zinc bath with 2% tin addition were investigated. The processes of hot dip metallization were carried out at 450°C temperature and immersion time of 180 s. It can be observed that the stress value can affect the behaviour of metal during the hot dip metallization process. Coated samples were analysed on a light microscope to specify the possibility of the occurrence of LME. These studies provided the basis for the selection of samples and areas for further quantitative andqualitative analysis on a scanning electron microscope (SEM) with a microanalysis system. The analysis of cracks in three microareas revealed that the tin content in the front of a fracture is twice as big as it is in other measuring points. It may be related to crack propagation due to the phenomenon of LME, by the accumulation of the initiating element atoms and those propagating the fracture.

In the paper the results of tests on obtaining zinc coatings on chains produced of the 23MnNiCrMo5-2 steel of grades C and PW9 have been presented. The growth kinetics of coatings obtained in the traditional galvanizing process at the temperature of 450°C has been established. The structure of coatings obtained on chains of various grades has been developed. The chemical composition of structural components of the coating has be established. It has been determined that the obtained coatings are continuous and they are quite thick. No significant impact of the chain grade upon the structure of coating has been established, however, it has been observed that the thickness of coating slightly decreases as the grade increases.