Effect of carbon addition on functional and mechnical properties of the Ni3Al phase

Casting technology was applied and research was carried out on two alloys based on the Ni3Al phase with variable carbon content of 0,2 and 1,25 wt. % C, respectively. Resistance to abrasive wear, friction coefficient and Vickers microhardness were determined. Metallographic studies were conducted to examine the macrostructure and microstructure of the investigated alloys. An increase in resistance to abrasive wear and microhardness of alloy containing 1,25 wt. % C was observed. The coefficient of friction was determined, which for the alloy with increased carbon content was much lower than for the alloy containing 0,2 wt. % C. Structural changes were reported to have some effect on functional and mechanical properties of the examined alloys

Influence of the cooling rate on the corrosion resistance of duplex cast steel

The results of the influence of the cooling rate of the casting made of the acid-resistant ferritic - austenitic cast steel on the microstructure and corrosion resistance are presented in the paper. Samples cut out from the walls of the casting being cooled at the cooling rate of 3,2 - 0,5 ºC/s were used in the study. Different cooling rates create favorable conditions for the segregation processes lowering properties of castings. It was found, that differences in the polarization curves occur only in the more aggressive corrosive environment. The reason of such behaviour of cast steel is the segregation of elements dissolved in austenite and the difference in the volume fraction of ferrite and austenite in the walls of the different thickness

Inkjet Printing Infiltration of the Doped Ceria Interlayer in Commercial Anode-Supported SOFCs.

Single-step inkjet printing infiltration with doped ceria Ce0.9Ye0.1O1.95 (YDC) and cobalt oxide (CoxOy) precursor inks was performed in order to modify the properties of the doped ceria interlayer in commercial (50 × 50 × 0.5 mm3 size) anode-supported SOFCs. The penetration of the inks throughout the La0.8Sr0.2Co0.5Fe0.5O3-δ porous cathode to the Gd0.1Ce0.9O2 (GDC) interlayer was achieved by optimisation of the inks' rheology jetting parameters. The low-temperature calcination (750 °C) resulted in densification of the Gd-doped ceria porous interlayer as well as decoration of the cathode scaffold with nanoparticles (~20-50 nm in size). The I-V testing in pure hydrogen showed a maximum power density gain of ~20% at 700 °C and ~97% at 800 °C for the infiltrated cells. The latter effect was largely assigned to the improvement in the interfacial Ohmic resistance due to the densification of the interlayer. The EIS study of the polarisation losses of the reference and infiltrated cells revealed a reduction in the activation polarisations losses at 700 °C due to the nano-decoration of the La0.8Sr0.2Co0.5Fe0.5O3-δ scaffold surface. Such was not the case at 800 °C, where the drop in Ohmic losses was dominant. This work demonstrated that single-step inkjet printing infiltration, a non-disruptive, low-cost technique, can produce significant and scalable performance enhancements in commercial anode-supported SOFCs

The Role of Molybdenum in the Formation of the Microstructure and Properties of Al-Cu Alloys

The subject of the presented research is the influence of molybdenum on selected properties of alloys that are based on the Al-Cu system. It could be observed that the introduction of molybdenum to the multi-component alloy at levels of up to 0.5 wt.% showed increases in the degrees of undercooling ΔT along with the increasing contents of the introduced element. The addition of molybdenum contributed to the reduction of the size of the primary grains of the α(Al) phase. Molybdenum improved the strength of the alloy while achieving elongation at a significant level. This is an element that occurs in the alloy – both in the iron-manganese phases and in the segregates inside the grains. Most of the iron-manganese phases occurred in a more spheroidal form. Additionally, tests were carried out on higher molybdenum content in the alloy. The addition of the tested chemical element at a level of 1 wt.% caused the precipitation of the phases that contained molybdenum, which did not dissolve after heat treatment

Predicting Productivity Losses from Health-Related Quality of Life Using Patient Data.

OBJECTIVE: This paper estimates productivity loss using the health of the patient in order to allow indirect estimation of these costs for inclusion in economic evaluation. METHODS: Data from two surveys of inpatients [Health outcomes data repository (HODaR) sample (n = 42,442) and health improvement and patient outcomes (HIPO) sample (n = 6046)] were used. The number of days off paid employment or normal activities (excluding paid employment) was modelled using the health of the patients measured by the EQ-5D, international classification of diseases (ICD) chapters, and other health and sociodemographic data. Two-part models (TPMs) and zero-inflated negative binomial (ZINB) models were identified as the most appropriate specifications, given large spikes at the minimum and maximum days for the dependent variable. Analysis was undertaken separately for the two datasets to account for differences in recall period and identification of those who were employed. RESULTS: Models were able to reflect the large spike at the minimum (zero days) but not the maximum, with TPMs doing slightly better than the ZINB model. The EQ-5D was negatively associated with days off employment and normal activities in both datasets, but ICD chapters only had statistically significant coefficients for some chapters in the HODaR. CONCLUSIONS: TPMs can be used to predict productivity loss associated with the health of the patient to inform economic evaluation. Limitations include recall and response bias and identification of who is employed in the HODaR, while the HIPO suffers from a small sample size. Both samples exclude some patient groups