International Scientific Journals
of Scientific Technical Union of Mechanical Engineering "Industry 4.0"

This study presents the effect of carbonation on 1020 carbonate, low fatigue. The carbonation of the samples was carried out at a temperature of 900 ° C and at a variable time of 5-9 hours. After the process of carbonization, the process was carried out with a temperature of 500 ° C and 30 minutes. The hardness of the sample was tested before the Chemical heat treatment was 206.5 HB and the hardness of the carbonated samples at 900 ° C and at 5 hours was 209.3HB and the hardness of the carbonated samples at 900 ° C and for 6 hours was 209.5 HB. The carbonated sample salad was 900 ° C and 9 hours 211.4 HB. The boxes were heated at (850-900) ºC in an electric furnace for different durations or times. Fatigue was tested for samples before and after carbonation carburizing contributed to the improvement in fatigue strength in different proportions. The degree of improvement depended on the depth (thickness) of the hardened layer and on the microstructure of a carburized steel.

The paper is devoted to distance exams, as in that the focus is on mathematical disciplines. Some advantages are standing out, as well as significant disadvantages have been discussed. Current modern tools are considered, which are applied both in the preparation of students and in distance exams.

The new and modified method of experimental determination of the vessel weight and the coordinates of its center of gravity without launching using inflatable elastic containers are shown in this article.