Właściwosci mechaniczne tytanu wyciskanego hydrostatycznie

The mechanical properties of titanium Grade 2 subjected to the hydrostatic extrusion technique (HE) were investigated. The hydrostatic extrusion technique is a method which refines the titanium grains to a nano-metric size. Compared with coarse grained titanium (CG-Ti), nanocrystalline titanium (NC-Ti) is characterized by a much higher yield stress, tensile strength and microhardness. The yield stress of NC-Ti determined in tensile tests is higher than that measured in compression test. The Young modulus of NC-Ti is slightly lower than that of CG-Ti.Przedmiot badań stanowiły właściwości mechaniczne tytanu Grade 2 poddanego wyciskaniu hydrostatycznemu. Technika wyciskania hydrostatycznego jest metodą, która umożliwia rozdrobnienie ziarna tytanu do wielkości nano-metrycznej. W porównaniu z tytanem gruboziarnistym (CG-Ti), tytan nanokrystaliczny (NC-Ti) charakteryzuje się o wiele wyższą granicą plastyczności, wytrzymałości na rozciąganie oraz mikrotwardością. Granica plastyczności NC-Ti wyznaczona podczas testów rozciągania jest wyższa niż granica plastyczności wyznaczona w testach ściskania. Natomiast moduł Young'a nanokrystalicznego tytanu jest nieznacznie mniejszy niż moduł tytanu gruboziarnistego

Microstructure and properties of the intermetallic layers on the Ti-6Al-4V titanium alloy

W pracy przedstawiono wyniki badań mikrostruktury oraz właściwości mechanicznych warstw międzymetalicznych z układu Ti-Al wytwarzanych metodą duplex na dwufazowym stopie tytanu Ti-6Al-4V. Warstwy otrzymane były na drodze dyfuzji i składały się z podwarstw różniących się składem chemicznym. Zastosowana obróbka cieplna w warunkach wyładowania jarzeniowego zapewnia wzrost mikrotwardości oraz poprawę odporności na zużycie ścierne, co zwiększa obszar zastosowań stopów tytanu.The paper presents the results of the investigation of the microstructure of Ti-Al intermetallic layers obtained on a Ti-6Al-4V titanium alloy by the duplex method. It has been found that this surface engineering technique yields multi - layered coatings with diffusive character. The layer contains intermetallic phases from Ti-Al system and increased microhardness and wear resistance of the Ti-6Al-4V alloy. These advantageous properties widen significantly the application range of the titanium alloy

Some operational features of coating obtained with PACVD method

The main aim of presented work was the commencing the tests and analysis of the DLC type a:C:H coatings obtained with PACVD technique on the elements from Co-Cr-Mo alloys., among others: monitoring of structure changes, hardness measurement, estimation of the surface geometrical structure and tribologic tests. The analysis of surface structure and its elementary composition were estimated with the application of scanning SEM microscope, as well as TEM transmission microscope. The hardness of the elements with and without the coating was measured with the Matsuzawa micro hardness testing tester. Tribologic test of materials wear resistance was done with using T-01M apparatus ball-on-disc type, within a set of Al2O3 ball - disk from Co-Cr-Mo alloys with DLC coating, in technologically dry friction condition as well as with Ringer solution lubrication. Friction tests were conducted with using tester T-17, working in association: polymer pin made of high-molecular polyethylene PE - UHMW - plate from Co-Cr-Mo alloys with DLC coating with Ringer solution lubrication. The results obtained during mentioned above tests showed that the application of DLC coatings greatly enhances the operating features of the coated surfaces

Possibilities of using plasma techniques of surface engineering for modification of polymer membranes

Oceniano możliwości wykorzystania plazmy niskotemperaturowej do aktywowania warstwy wierzchniej membran polimerowych oraz deponowania na nich ultracienkich warstw metalicznych. Stwierdzono, że za pomocą takich technik inżynierii powierzchni możliwa jest skuteczna modyfikacja właściwości funkcjonalnych membran polimerowych, istotnych w zastosowaniach do wysokoefektywnego oczyszczania wód i ścieków.The paper discusses the possibilities of using low temperature plasma in activating the surface layer of polymer membranes and depositing ultra-thin metallic layers on their surface. It has been found that the above surface engineering techniques enable effective modification of functional properties of polymer membranes, which are important in high-efficiency water and wastewater treatment

Surface engineering techniques used for improving the mechanical and tribological properties of the Ti6A14V alloy

The microstructure, mechanical and tribological properties of composite intermetallic layers of the Ti-Al system were investigated. The layers on the two-phase (alpha+beta) Ti6A14V titanium alloy were obtained using the hybrid method, which consist of two stages. First, the titanium alloy was covered with aluminum layer by magnetron sputtering. In the second stage, coated specimens were treated under glow discharge conditions. The surface treatment makes it possible to obtain the diffusional composite layers which considerably improve the mechanical and wear resistance properties of the material. These properties cannot be achieved using simple methods of surface engineering. The chemical and phase composition of the composite intermetallic layers was investigated. It has been shown that the hybrid method significantly increases the hardness and wear resistance of the titanium alloy and can widen the range of application of the material. Because of the diffusional character of the intermetallic layers they possess good adhesion to the titanium substrate