Dear Prof. Barkey, How many data points need to consider for Plastic strain vs. no. of reversals to failure curve? Is it till row no. 16? The entry for plastic strain in row no. 17 is zero, and what happens to the data point in the row no. 18? In the case of the elastic curve, I think all the data points have been considered. For this curve, I can see that the R^2 =1, However, with the same data I am getting y=0.0036 X^-0.077 and R^2= 0.656. It would be really helpful if you could tell me what am I missing here? How to get the extrapolated curve (Series 7) for total strain vs. no. of reversals to failure? Thanks and Regards, KB
Hi Kamanasish, It has a year--so I don't recall all of the specifics. But the series 7 line is just the strain life equation, probably using 1 to 1,000,000 reversals to calculate the corresponding strain amplitude, using the fits I determined. Keep in mind that all curve fits have a limited range of applicability and are influenced by the data that is used or not used in the fit.
Dear Prof. Barkey,
How many data points need to consider for Plastic strain vs. no. of reversals to failure curve? Is it till row no. 16?
The entry for plastic strain in row no. 17 is zero, and what happens to the data point in the row no. 18?
In the case of the elastic curve, I think all the data points have been considered. For this curve, I can see that the R^2 =1, However, with the same data I am getting y=0.0036 X^-0.077 and R^2= 0.656. It would be really helpful if you could tell me what am I missing here? How to get the extrapolated curve (Series 7) for total strain vs. no. of reversals to failure?
Thanks and Regards,
KB
Hi Kamanasish, It has a year--so I don't recall all of the specifics. But the series 7 line is just the strain life equation, probably using 1 to 1,000,000 reversals to calculate the corresponding strain amplitude, using the fits I determined. Keep in mind that all curve fits have a limited range of applicability and are influenced by the data that is used or not used in the fit.
Dear Prof. Barkey,
I am wondering if you can kindly share the data sheet so that we can practice by ourselves as well.
Thanks a lot,
Hamid
there are not so many values--please see 1:15
We need more information please
such as ?