In the process chain of heat-treated components of STIWA Automation GmbH, problems with product qualities and too high production costs were identified. That is why an analyse of these processes in terms of quality and cost-effectiveness around heat treatment was necessary. These treatments are done by an external supplier. The ordering process was analysed by interviews between the company's internal and external employees as well as order data from two financial years. In addition, an ABC analysis was carried out regarding the costs and quantities of used materials. This resulted in a high dominance of only two materials, which account for about 80 % of the quantities. 15 further materials should be examined for rationalization potentials, as they cause high heat treatment costs in the ordering process due to low order volumes. Some of the standardised heat treatments are hardly used. The share of six materials is greater than a quarter. These lead to high costs, which can be reduced either by rationalizing or extending standards. In addition, a considerable variability in order volumes was shown. The weekly number of order positions mostly used materials varies by an average of 25 %. Smoothing these spikes would avoid wasting. Deliveries sent to the service provider are often split, despite identical heat treatment. Therefore, additional costs arise by falling below the minimum order or volume discount limits. Theoretically, the possible potential savings for the most ordered material equals a quarter of the costs. It has also been experienced that components for heat treatments, which can only be done by the supplier once a week, are immediately sent to the supplier. However, these are billed as individual deliveries, although they are then heat treated on the same day of the week. The optimization potential is a more time-accurate order, so that the heat treatment costs do not multiply. Finally, the number of standardised heat treatments could be rationalised in the ordering system. The combination of heat treatments of the same hardening and tempering temperatures, but different materials, would be technologically possible and should therefore be examined in coordination with the supplier. Due to the lack of internal quality tests regarding the hardness of the tool steels, a sample was performed by hardness tests. The test according to Vickers was used. Moreover, the determined values were then re-evaluated in hardness values according to Rockwell. Measurement uncertainty was determined and included in the assessment. The sample of 85 parts showed that the hardness values are normal distributed on average around the upper tolerance level and have a high variation. Statistically at least 29 % are out of order, and 36 % are fine. Results of suppliers routine tests illustrated a tendency towards higher values as well. Obviously, the distribution is uneven, shown by an abruptly drop to zero at the upper tolerance level. This suggests an irregular rounding of hardship levels.