Modern Approaches in Design Optimization of Parts and the Development Trend of Surface Treatments

This paper summarizes the surface engineering technologies having a substantial contribution to increasing operational performance of the parts as well as current trends in the implementation of surface processing technologies that imply technical benefits and minimum negative impact on the environment The experimental results illustrate the influence of during superficial thermal treatment by high frequency current heating and thermochemical treatment (ionic nitriding) on the structural and physic - mechanical characteristics of heat treatable steel pieces. Also experimental results allowed conclusions on optimal regimes of surface processing and comparative analysis of properties obtained through different methods of processing

Researches regarding the thermomechanical treatments influence on the structure and characteristics of the aluminium alloys for aeronautics

The laboratory experiments were made on the two aluminium alloyed qualities used for aeronautical industry. More working conditions of the intermediary (PTMI) and finally (PTMF) thermomechanical treatments were used on the industrial rolled test-specimen. Also, the conventional thermal treatment was used, consisting of the solution quenching and artificial heat ageing, mode in more working condition, test. The structure and mechanical characteristics were analyzed and the gotten results were compared using those two types of the thermal and thermomechanical treatments. A significantly improvement of the mechanical characteristics was ascertained to the thermomechanical treated test-specimen

Study of the Inclusions from the Oriented Grains Silicon Steels and their Influence on the Texture

The paper presents experimental results concerning the inhibitor phases generation by microalloying elements utilization. It was made experiments on three silicon steel charges. It was observed that the inhibitor phases have a strong influence on steel sheet structure and its texture. So these phases can by considered like “texture nucleus”

The Dental Technology in Art Foundry

The paper presents results of a study undertaken to implement the dental casting technique of small parts characterized by extremely complex drawings of surfaces and thicknesses reduced specific objects. During the study there was a similarity between this technique and casting forms obtained with models used to obtain spare fuses in the car industry. They could highlight differences between the materials and the equipment used in dental technology and art foundries

Magnetical Properties of Silicon Steels Used for Electrotechnical Industries

This paper-work shows the laboratory experiments achieved on more silicon steel plates, where the magnetic ranges were spot- lighted by particular technical requirements. On the same plates the texture analyses were made considering Goss characteristics, shape and orientation of the crystalline grains, too. Finally, a correlation between texture, structure and magnetic characteristics was gotten

Intercritical Thermomechanical Treatments of the Microalloyed Steel Products for Welded Structures

This paper shows the laboratory experiments made on several grade steels by applying some intercritical thermomechanical treatments; Two variants were used: “down-up” thermomechanical treatment with heating and rolling in the  intercritical range and “up-down” thermomechanical treatment with preliminary complete austenitizing and rolling in the intercritic interval. Structural changes, as well as changes of properties revealed in the experimental variants of the intrercritical treatment, have been compared to those revealed by controlled rolling and normalization states of delivery that are recommended to flat products from these steel grades. High values of the strength characteristics and a good plasticity have been obtained. The paper presents only a part of the results obtained when applying different regimes of thermal and thermomechanical treatment within experimental researches made at laboratory and industrial scale, on thick plates of different thicknesses and qualities of the weldable steels

Researches Regarding Waste Processing of Cellulosic Materials by Pyrolysis Process

In this paper were performed laboratory experiments regarding processing by pyrolysis process of urban waste components (wood, paper, textiles). The authors designed and developed an experimental equipment and were applied several technological parameters such as temperature and plant maintenance time. The analysis of physical and chemical properties of obtained products found that pyrolysis process can be an effective alternative treatment of urban waste to reduce their quantity and to increase environmental protection

Thermomechanical Processing of Microalloyed Steels Used for Naval and Oil Industries

This paperwork shows the laboratory experiments made on X60 and X65 steels with several intercritical thermomechanical treatment application. Two variants were used: “down-up” thermomechanical treatment with heating and rolling in the intercritical range and “up-down” thermomechanical treatment with preliminary complete austenitizing and rolling in the intercritic interval. High values of the strength characteristics and a good plasticity were gotten. A comparison was made with gotten results of the classical thermal treatment application (normalizing)

Study on the Influence of the Chemical Composition in the Thermomechanical Processing of the Steel Products

This paper presents the results of industrial scale researches on the influence of the chemical composition on the characteristics of high yield point plates of wieldable fine grain steels. The comparative study of the mechanical characteristics obtained by the classical process and by the controlled rolling process point out the possibility of replacing the classical heat treatment for some steel grades, for plates used metallic structures in railway bridges, high tornage travelling cranes, marine platform bases, high pressure vessels, etc

Researches Regarding Improvement of the Fatigue Limit by Heat Treatments of the Al-Alloys for Aeronautics Industry

The laboratory experiments were made on the two aluminium alloyed qualities used for aeronautical industry. The structure and mechanical characteristics were analyzed and the gotten results were compared using those two types of the thermal treatments. Also, the conventional thermal treatment was used, consisting of the solution quenching and artificial heat ageing, mode in more working condition. A significantly improvement of the mechanical characteristics was ascertained  to the thermical treated test-specimen