Methods and techniques of samples preparation for assessment of layers after chemical and heat treatment
Unsuitable technique of metallographic preparation of samples and components after various chemical and heat treatment could have decisive effect on the final properties and conditions of investigation layers. Also, an incorrect preparation process has considerably influence on the cost of preparation of sample. In case of cutting of different study materials is possible to do micro-cracks which could be incorrect evaluated. The micro cracks could be wrong attributed to chemical and heat treatment technology too. In the current work a description and a wide discussion about the most suitable and proven process for the preparation of metallographic samples is treated at the same time that the main methods of chemical and heat treatment are discussed.
The aim of this paper is to do a review about modern and proven methods and procedures for preparation of samples and its subsequent assessment of them layers, doing a comparison with the principal methods for chemical attaching and heat treatment used in the industry. This work is also focused on correct technique of sampling from components with layer and are given some suggestions for selection of expendable supplies. A Discussion about the correct observation methods, measurement of thickness in the layers and its hardness is mentioned. All the methods are suggested according to technical standards. Add in the present work, suitable and unsuitable measurements of micro hardness are involved. For layers with very low thickness, one section about the selection of load test for mechanical properties is included.