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The VHCF behaviour of metallic materials containing microstructural defects such as non-metallic inclusions is determined by the size and distribution of the damage dominating defects. In the present paper, the size and location of about 60.000 inclusions measured on the longitudinal and transversal cross sections of AISI 304 sheet form a database for the probabilistic determination of failure-relevant inclusion distribution in fatigue specimens and their corresponding fatigue lifes. By applying the method of Murakami et al. the biggest measured inclusions were used in order to predict the size of failure-relevant inclusions in the fatigue specimens. The location of the crack initiating inclusions was defined based on the modeled inclusion population and the stress distribution in the fatigue specimen, using the probabilistic Monte Carlo framework. Reasonable agreement was obtained between modeling and experimental results.

The formation of the PbTe quantum dots (QDs) in a crystalline CdTe host by the annealing of a coherent, heteroepitaxial PbTe layer clad between CdTe layers is demonstrated. It is observed that QDs have a centrosymmetric shape and they exhibit intense room-temperature mid-infrared photoluminescence due to an electron-hole pair recombination in the narrow-gap PbTe.

Although ice fracturing and deformation is key to understanding some of the landforms encountered in the high‐latitude regions on Mars and on other icy bodies in the solar system, little is known about the mechanical characteristics of CO 2 ice. We have measured the hardness of solid CO 2 ice directly in the laboratory with a Leeb hardness tester and calculated the corresponding yield strength. We have also measured the hardness of water ice by the same method, confirming previous work. Our results indicate that CO 2 ice is slightly weaker, ranging between Leeb ∼200 and 400 (∼10 and 30 MPa yield strength, assuming only plastic deformation and no strain hardening during the experiment), for typical Martian temperatures. Our results can be used for models of CO 2 ice rupture (depending on the deformation timescales) explaining surface processes on Mars and solar system icy bodies. Plain Language Summary: We have measured the hardness and calculated the strength of dry (carbon dioxide) ice. It is slightly weaker than water ice in the temperature range that can be found on Mars. Our results can be used in models of how surface features on Mars and on other icy surfaces in the solar system are formed. Key Points: We have measured the hardness of CO 2 ice in Martian temperaturesWe derived the corresponding yield strength valuesUnder Martian conditions CO 2 ice is slightly weaker than H 2O ice [ABSTRACT FROM AUTHOR]

We present rock-salt IV-VI semiconductor quantum dots fabricated by implantation of Pb+, Te+, or Sn+ ions into epitaxial zinc-blende CdTe layers. PbTe and SnTe nanoprecipitates of high structural quality are formed after implantation by thermal annealing due to the immiscibility of dot and matrix materials. For samples implanted only with Pb+, intense continuous-wave photoluminescence peaked at 1.6 μm at 300 K is found. In contrast, for PbTe quantum dots fabricated by coimplantation of Pb+ and Te+, the 300 K emission peak is observed at 2.9 μm, indicating luminescence from much larger dots. [ABSTRACT FROM AUTHOR]