The motion of intervariant intedeces under the action of applied stress in the internally faulted 18R martensite in a Cu-Zn-Al shape memory alloy has been studied. Transmission electron microscopy in situ observations...The motion of intervariant intedeces under the action of applied stress in the internally faulted 18R martensite in a Cu-Zn-Al shape memory alloy has been studied. Transmission electron microscopy in situ observations show that the interfaces between 24 martensite variants have different reaction to applied stress. The A/C type and A/B type interfaces have good mobil-ity, the A/D type interface has bad mobiIity, and the different-group-intervariant interfaces are basically immobile.展开更多
It is important to understand the correlation between grain morphology and intervariant boundaries of theαphase after heat treatment belowβtransus of the electron beam melted(EBMed)Ti-6 Al-4 V alloy.Scanning electro...It is important to understand the correlation between grain morphology and intervariant boundaries of theαphase after heat treatment belowβtransus of the electron beam melted(EBMed)Ti-6 Al-4 V alloy.Scanning electron microscopy(SEM)and electron backscatter diffraction(EBSD)analysis have shown about 99%αphase and 1%βphase in the heat-treated samples when the temperature rises to 950℃.Four distinct types ofαgrain morphology have been found:allotromorphousα,relatively coarseαplate,large precipitationαand granularα.A single peak of the intervariant boundary with the misorientation of 60°/[1120]associated with Burgers orientation relationship(OR)was found in the allotromorphousαcolony.Multiple intervariant boundaries mixed with a fraction of general high-angle grain boundary(GHABs,not Burgers OR)were present in the relatively coarseαplate colony.Almost only low-angle grain boundaries(LABs)with the misorientation of<5°were found in the large precipitationαgrains.βphase tends to distribute around the boundaries of relatively coarseαplates.It suggests that different formation mechanisms are involved in the distinct types ofαgrain morphology.展开更多
Detailed crystallographic analysis has been undertaken on the various combinations Of 24 martensite variants in the 18R martensite of a Cu-Zn-Al shape memory alloy. Based upon the calculated crystallographic data, the...Detailed crystallographic analysis has been undertaken on the various combinations Of 24 martensite variants in the 18R martensite of a Cu-Zn-Al shape memory alloy. Based upon the calculated crystallographic data, the interface energy of different twin interfaces was calculated using a lowangle-grain-interface model. For the variant/variant pairs in a self-accommodating group. the A/C type and A/B type interfaces have low interface energy, and A/D type interface is an intermediate one. In contrast, the intervariant interfaces that belong to different plate groups have high intrface energy. The calculated results are consiStent with the previous observations of the mobility of intervariant interfaces.展开更多
Background:Variation in the speech of speakers is a crucial issue for the forensic system.The main reason behind incorrect speaker identification is greater intra-speaker fluctuation.In the forensic state of play,a lo...Background:Variation in the speech of speakers is a crucial issue for the forensic system.The main reason behind incorrect speaker identification is greater intra-speaker fluctuation.In the forensic state of play,a lot of research has been carried out on speaker identification.However inter variations and intra fluctuations in speakers for the Punjabi language is still a grey area.Aims and Objectives:Our aim is to study acoustic analysis of fluctuations for inter and intra speaker variability in speech sounds.In our study,we will consider Punjabi vowel with consonants.The Statistical methods will be applied to analyze the data;firstly,the Shapiro-Wilk test will be checked for normality and then Levene’s Test to assess the equality of variances.Materials and Method:Five vowels were selected with different consonants.They were combined to make meaningful words.Then these meaningful words were embedded in sentences.Ten speakers participated voluntarily.All are students of A.S College at Khanna in Punjab.The individuals were aged between 20-22 years with no hearing or speech disorder.The voice samples were recorded with help of good quality microphone and by Goldwave software in the sound proof lab.Samples were introduced directly into PRAAT software by the use of a Sony microphone and with sampling rate of 44100 Hz frequency.Acoustic Analysis has been done with help of Goldwave software in form of spectrograms.Results and Conclusion:Each formant shows a different value for inter variations and inter speaker fluctuations.F1 and F2 shows lesser speaker variation than the high-frequency region in F3 and F4,so we can say that in comparison with the lower part,high-frequency regions are more valuable.The assumptions for TWO-WAY ANOVA is violated and hence,we have used the non-parametric Friedman Test and performed its Post hoc analysis.From Posthoc analysis,we can say that F1 and F2(p>0.05)and F2 and F3(p>0.05)gave the same type of results.Hence,from the results of these statistical tests,we can conclude that F1 is recommended over F2,F3,and F4.As the frequency of F1 is high as well as in line with the results of statistical tests.Because we prefer more variation among frequencies so that we can easily distinguish different speakers and it would be more beneficial for inter variations and intra fluctuations.展开更多
文摘The motion of intervariant intedeces under the action of applied stress in the internally faulted 18R martensite in a Cu-Zn-Al shape memory alloy has been studied. Transmission electron microscopy in situ observations show that the interfaces between 24 martensite variants have different reaction to applied stress. The A/C type and A/B type interfaces have good mobil-ity, the A/D type interface has bad mobiIity, and the different-group-intervariant interfaces are basically immobile.
基金financially supported by the Key R&D Plan of the Ministry of Science and Technology(No.2018YFB1105900)the Shandong Province Key R&D Project(No.2018GGX103017)the Zibo City and SDUT Integration Project(No.2018ZBXC154)。
文摘It is important to understand the correlation between grain morphology and intervariant boundaries of theαphase after heat treatment belowβtransus of the electron beam melted(EBMed)Ti-6 Al-4 V alloy.Scanning electron microscopy(SEM)and electron backscatter diffraction(EBSD)analysis have shown about 99%αphase and 1%βphase in the heat-treated samples when the temperature rises to 950℃.Four distinct types ofαgrain morphology have been found:allotromorphousα,relatively coarseαplate,large precipitationαand granularα.A single peak of the intervariant boundary with the misorientation of 60°/[1120]associated with Burgers orientation relationship(OR)was found in the allotromorphousαcolony.Multiple intervariant boundaries mixed with a fraction of general high-angle grain boundary(GHABs,not Burgers OR)were present in the relatively coarseαplate colony.Almost only low-angle grain boundaries(LABs)with the misorientation of<5°were found in the large precipitationαgrains.βphase tends to distribute around the boundaries of relatively coarseαplates.It suggests that different formation mechanisms are involved in the distinct types ofαgrain morphology.
文摘Detailed crystallographic analysis has been undertaken on the various combinations Of 24 martensite variants in the 18R martensite of a Cu-Zn-Al shape memory alloy. Based upon the calculated crystallographic data, the interface energy of different twin interfaces was calculated using a lowangle-grain-interface model. For the variant/variant pairs in a self-accommodating group. the A/C type and A/B type interfaces have low interface energy, and A/D type interface is an intermediate one. In contrast, the intervariant interfaces that belong to different plate groups have high intrface energy. The calculated results are consiStent with the previous observations of the mobility of intervariant interfaces.
文摘Background:Variation in the speech of speakers is a crucial issue for the forensic system.The main reason behind incorrect speaker identification is greater intra-speaker fluctuation.In the forensic state of play,a lot of research has been carried out on speaker identification.However inter variations and intra fluctuations in speakers for the Punjabi language is still a grey area.Aims and Objectives:Our aim is to study acoustic analysis of fluctuations for inter and intra speaker variability in speech sounds.In our study,we will consider Punjabi vowel with consonants.The Statistical methods will be applied to analyze the data;firstly,the Shapiro-Wilk test will be checked for normality and then Levene’s Test to assess the equality of variances.Materials and Method:Five vowels were selected with different consonants.They were combined to make meaningful words.Then these meaningful words were embedded in sentences.Ten speakers participated voluntarily.All are students of A.S College at Khanna in Punjab.The individuals were aged between 20-22 years with no hearing or speech disorder.The voice samples were recorded with help of good quality microphone and by Goldwave software in the sound proof lab.Samples were introduced directly into PRAAT software by the use of a Sony microphone and with sampling rate of 44100 Hz frequency.Acoustic Analysis has been done with help of Goldwave software in form of spectrograms.Results and Conclusion:Each formant shows a different value for inter variations and inter speaker fluctuations.F1 and F2 shows lesser speaker variation than the high-frequency region in F3 and F4,so we can say that in comparison with the lower part,high-frequency regions are more valuable.The assumptions for TWO-WAY ANOVA is violated and hence,we have used the non-parametric Friedman Test and performed its Post hoc analysis.From Posthoc analysis,we can say that F1 and F2(p>0.05)and F2 and F3(p>0.05)gave the same type of results.Hence,from the results of these statistical tests,we can conclude that F1 is recommended over F2,F3,and F4.As the frequency of F1 is high as well as in line with the results of statistical tests.Because we prefer more variation among frequencies so that we can easily distinguish different speakers and it would be more beneficial for inter variations and intra fluctuations.
