Nonlinear Acoustic Response in thin Oxide Layers on Fused Silica

1996 ◽  
Vol 436 ◽  
Author(s):  
C. R. Ottermann ◽  
S. U. Fassbender ◽  
W. Arnold ◽  
K. Bange

AbstractNonlinear mechanical properties of layered systems of Ta2O5 and TiO2 films deposited on fused silica by reactive evaporation (RE), reactive ion plating (IP) and spin coating (SC) are investigated by means of an ultrasonic technique. The coatings with thickness of 100 nm possess differences in density and crystal structure, due to the different deposition conditions. The nonlinear acoustic response of the film/substrate systems depends on film material. Differences are observed in respect to film density as obtained by the alternate deposition methods. The origin of the differences in nonlinear acoustic response of the samples is discussed. The results are correlated to adhesion properties of the films determined by a scratch-test method.

1994 ◽  
Vol 356 ◽  
Author(s):  
C. R. Ottermann ◽  
Y. Tomita ◽  
M. Ishiyama ◽  
K. Bange

AbstractAdhesion of oxidic and metallic films with thicknesses between 40 nm and 350 nm has been investigated by means of a scratch-test method based on a vibrating diamond micro-indenter. SiO2 and TiO2 films are precipitated on fused silica substrates by sol-gel techniques (SG), reactive evaporation (RE), reactive low-voltage ion plating (IP), and plasma impulse chemical vapour deposition (PICVD), and Cr-layers are produced by rf magnetron sputtering (SP). The influence of aging effects on film adhesion is investigated in respect of several conditions, like storage under ambient surroundings with differences in relative humidity or temperature treatment. A method is presented allowing control of the long-term stability of the scratch-test conditions. Temperature treatment up to 600 °C is found to have the most significant impact on adhesion properties. Adhesion increases for some SiO2 films, whereas for TiO2 layers an opposite behavior is observed. Here, the adhesion of the originally amorphous titania films is reduced due to the phase transition to polycrystalline anatase, which correlates with a significant increase in film stress.


1993 ◽  
Vol 308 ◽  
Author(s):  
C. Ottermann ◽  
N. Tadokoro ◽  
Y. Tomita ◽  
K. Bange

ABSTRACTAdhesion of Cr, SiO2, TiO2 and Ta2O5 films with thicknesses between 40 nm and 380 nm has been investigated using a new scratch-test method based on a vibrating diamond micro-indenter. The oxide films are produced on different substrates by sol-gel technique (SG), reactive evaporation (RE), reactive ion plating (IP) and plasma impulse chemical vapor deposition (PICVD); Cr-layers are deposited by sputtering (SP) on quartz. Large variations in adhesion are found for different coating techniques and deposition conditions, especially the substrate temperature. The adhesion can be correlated with microscopic properties in the film-substrate interface where differences are analyzed in term of hydrogen content, film growth and density. The adhesion is also connected with other macroscopic film quantities.


2015 ◽  
Vol 237 ◽  
pp. 15-20 ◽  
Author(s):  
Jerzy Smolik ◽  
Adam Mazurkiewicz ◽  
Zbigniew Słomka ◽  
Jan Bujak ◽  
Joanna Kacprzyńska-Gołacka ◽  
...  

Based on the analysis of the research directions in the field of coatings and layers with special operating properties, the production technologies of composite coatings, including the gradient, multi-layer, and multi-component coatings, should be distinct. The paper presents the results of material properties tests of a multi-layer coating Ti / TiN / TiAlNgradient / (TiAlN/VN)multinano obtained on hot working steel EN X32CrMoV3.3. The preparation of the multilayer coating was specially designed to increase the durability of forging dies in the brass forging process. The authors discuss the results of the microstructure tests for the obtained coatings (STEM+FIB) and present the hardness and Young's modulus as a function of the distance from the surface (nanoHardness Tester CSM) and the results of adhesion tests carried out using a scratch-test method. The obtained multilayer coatings were also subject to a tribological test using a tribometer tester by DUCOM. The authors indicate that the coatings based on vanadium nitride have very high hardness and Young's modulus (HV = 32–35 GPa, E = 420–450 GPa), a much lower coefficient of friction in combination with brass than steel, and a lower stability of these parameters at elevated temperatures. According to the authors, the coating represents an interesting material solution to increase the durability of forging dies in the process of brass forging.


1990 ◽  
Vol 188 ◽  
Author(s):  
M. Ignat ◽  
A. Chouaf ◽  
Ph. Normandon

ABSTRACTThe evolution of internal stresses in Tungsten films deposited on Silicon substrates submitted to external stresses is discussed here. The stresses are estimated and measured by theoretical and experimental methods. The discussion of the internal stress evolution is shown to be dependent of the film/substrate interfaces, and of the loss of adhesion inducing stress relaxation.


1993 ◽  
Vol 308 ◽  
Author(s):  
Ru Wang

ABSTRACTThe validity of Lc of film failure is studied with friction — detected scratch test . The specimens used in the experiment are ion-plated TiN and Ti films,Chemical-Plated NiPCu films on steel of various hardness,ion beam mixed plated TiN films on optical glass,The morphology of failed films was studied under optical microscope and scanning electronmicroscope,The composition of starting failure of films was analyzed with electro — probe. It is found that in the curves of scratch tests of ion-plated TiN and Ti films on high-speed steel,the load corresponding the sudden change of the horizontal force is the same as the critical load of film failure,however,the critical load obtained in the scratch test of the ion-plated TiN and Ti films on soft steel is the some deference compared with optical microscope analyzed, that is principally due to the property of films and substrates (hardness and coefficient).The morphology and mechanism of ion — plated TiN and Ti films on high —speed steel are also studied in the paper.The adhesion between film and substrate is an effective method in evaluating the films property. After apprasing the effectiveness of acoustic emission monitoring scratch test, someone think that no matter coated with hard or soft film it is effective on the brittle hard substrate. However,there exist errors to different extent on other film-substrate system,and the scratch test is inapplicable for soft film-soft substrate system[1]. P. A. Steinmann pointed out while studying the factors influnceing the critical load Lc,that friction coefficient is a key factor on Lc,it provided valuable information in measuring Lc,but it think it is imporsible to measure Lc totally dependent on sudden change friction or friction coefficient, howeveer, for a specific coating substrate system,it is acceptable to say that Lc is dependent on friction coefficient[2]. This paper study experimentally on the friction detected scratch test and found out that effectiveness of Lc varies substantially in different film-substrate system. The author studiied the regularity of various system and discuse the season. The failure morphology and principles of ion-plated TiN and Ti film on highspeed steel are also analyzed in this paper.


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