# Copyright (c) 2019-2023 - for information on the respective copyright owner
# see the NOTICE file and/or the repository
# https://github.com/boschresearch/pylife
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
__author__ = "Simone Schreijäg"
__maintainer__ = "Johannes Mueller"
import numpy as np
[docs]
def true_strain(tech_strain):
"""
Calculation of true strain data (from experimental data generated by tensile experiments)
Parameters
----------
tech_strain: array-like float
Returns
-------
true_strain: array-like float
"""
return np.log(1. + tech_strain)
[docs]
def true_stress(tech_stress, tech_strain):
"""
Calculate the true stress data from technical data
Parameters
----------
tech_stress : array-like float
stress data from tensile experiments
tech_strain : list of float
strain data from tensile experiments
Returns
-------
true_stress : array-like float
"""
return tech_stress * (1. + tech_strain)
[docs]
def true_fracture_strain(reduction_area_fracture):
"""
Calculation of the true frature strain (in the FKM Non Linear (static assessment))
Parameters
----------
reduction_area_fracture : float
directly measured on the fractures sample
Returns
-------
true_fracture_strain: float
descrivbes the calculated true fracture strain.
"""
return np.log(1./(1. - reduction_area_fracture))
[docs]
def true_fracture_stress(fracture_force, initial_cross_section, reduction_area_fracture):
"""
Calculation of the true fracture stress (euqation FKM Non-linear (static assessment))
Parameters
----------
fracture_force : float
from experimental results
initial_cross_section : float
cross section of initial tensile sample.
reduction_area_fracture : float
directly measured on the fractures sample.
Returns
-------
true_fracture_stress: float
calculated true fracture stress of the sample.
"""
return fracture_force/(initial_cross_section * (1. - reduction_area_fracture))