More Like this

1. Type IV failure in weldment of creep resistant ferritic alloys: II. Creep fracture and lifetime prediction

   https://doi.org/10.1016/j.jmps.2019.103775  

   Zhang, Wei; Wang, Xue; Wang, Yiyu; Yu, Xinghua; Gao, Yanfei; Feng, Zhili (January 2020, Journal of the Mechanics and Physics of Solids)
2. Web Length Creep in Wound Rolls

   Mollamahmutoglu, C.; Gajjalla, A.; Markum, R.; Azoug, A.; Good, J.K. (June 2019, Proceedings of the Fifteenth International Conference on Web Handling)

   For convenience, webs are stored in wound rolls. The available web length in a wound roll is one mark of roll quality and a concern for many who process and convert webs. Elastic winding models have proven very precise at estimating the number of layers, the web length wound into a roll, and the residual stresses in the roll at the time of winding. Wound rolls can spend long periods of time in storage, where controlling the environment is cost-prohibitive. As many webs are viscoelastic on some time scale, the residual stresses due to winding will result in creep during storage. The changes in web length due to creep result in web process errors and quality loss, including registration errors and camber webs for example. This publication will focus on the development of a viscoelastic winding model to predict these changes in web length due to creep in a wound roll. The viscoelastic model predicts the tangential stress relaxation and radial creep due to winding residual stresses from a fully viscoelastic orthotropic material behavior. A spunned-meltblown-spunned (SMS) web and a low-density polyethylene (LDPE) web are taken as examples of viscoelastic webs. Their viscoelastic properties are systematically characterized using creep experiments. The results of the model show good agreement with winding and storage experiments for both webs. Finally, webs often do not creep uniformly across their width. An example of this non-uniform creep will be explored. 

   more » « less
3. Mechanisms of creep in shale from nanoscale to specimen scale

   https://doi.org/10.1016/j.compgeo.2021.104138  

   Yin, Qing; Liu, Yingxiao; Borja, Ronaldo I. (August 2021, Computers and Geotechnics)

   null (Ed.)
4. Effects of pressure on diffusion creep in wet olivine aggregates

   https://doi.org/10.1016/j.pepi.2022.106840  

   Silber, Reynold E.; Girard, Jennifer; Karato, Shun-ichiro (March 2022, Physics of the Earth and Planetary Interiors)
5. Creep and recovery in dense suspensions of smooth and rough colloids

   https://doi.org/10.1122/8.0000722  

   Saraswat, Yug Chandra; Kerstein, Eli; Hsiao, Lilian C (March 2024, Journal of Rheology)

   We report the effect of particle surface roughness on creep deformation and subsequent strain recovery in dense colloidal suspensions. The suspensions are composed of hard-spherelike poly(methyl methacrylate) smooth (S) and rough (R) colloids with particle volume fractions ϕS = 0.64 ± 0.01 and ϕR = 0.56 ± 0.01, corresponding to a distance of 3.0% and 3.4% based on their jamming volume fractions (ϕJS=0.66±0.01, ϕJR=0.58±0.01). The suspensions are subject to a range of shear stresses (0.01–0.07 Pa) above and below the yield stress values of the two suspensions (σyS=0.035Pa, σyR=0.02Pa). During creep, suspensions of rough colloids exhibit four to five times higher strain deformation compared to smooth colloids, irrespective of the applied stress. The interlocking of surface asperities in rough colloids is likely to generate a heterogeneous microstructure, favoring dynamic particle activity and percolation of strain heterogeneities, therefore resulting in higher magnitude of strain deformation and an earlier onset of steady flow. Strain recovery after the cessation of stress reveals a nonmonotonic recoverable strain for rough colloids, where the peak recoverable strain is observed near the yield stress, followed by a steep decline with increasing stress. This type of response suggests that frictional constraints between geometrically frustrated interlocking contacts can serve as particle bonds capable of higher elastic recovery but only near the yield stress. Understanding how particle roughness affects macroscopic creep and recovery is useful in designing yield stress fluids for additive manufacturing and product formulations. 

   more » « less