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Abstract The austempered ductile iron (ADI) with carbides in its microstructure, commonly known as CADI, is a relatively new variant of ductile iron intended to resist abrasive wear in different tribosystems by selecting the appropriate casting procedure, chemical composition and heat treatment. In this case, the rolling contact fatigue (RCF) behavior of CADI with two heat treatments was compared to that of ADI to evaluate its potential use as an alternative material for machine parts subjected to point or line rolling/sliding contact fatigue conditions. The RCF tests were done in a flat washer type testing machine under contact conditions (load, roughness, lubricant and velocity) leading to contact of micro-asperities. When compared to ADI, the microstructure of CADI has similar nodularity and nodule size, but the nodule count is lower because part of the carbon is combined in the form of carbides. While having similar hardness and failure appearance, CADI RCF resistance was higher than that of ADI. It was observed that the nodules at or near the surface work as crack nucleation sites and then, when replacing part of the graphite content with carbides the load carrying capacity and the RCF resistance are improved with respect to those of ADI. Highlights • Heterogeneous materials under RCF perform different than homogeneous materials. • In general, CADI performed better than ADI under RCF conditions. • Compliant inclusions as micro-voids and graphite are very harmful for RCF life. • Carbide inclusions are less harmful than graphite for RCF performance. • Carbide reinforcement increased hardness and load carrying capacity. [ABSTRACT FROM AUTHOR]

Abstract: The purpose of this work is to present a new computational tool for ionogram generated with a Canadian Advanced Digital Ionosonde (CADI). This new tool uses the fuzzy relation paradigm to identify the F trace and from this form extract the parameters foF2, h′F, and hpF2. The tool was very extensively tested with ionosondes that operate at low latitudes and near the equatorial region. The ionograms used in this work were recorded at São José dos Campos (23.2° S, 45.9° W; dip latitude 17.6° S) and Palmas (10.2° S, 48.2° W; dip latitude 5.5° S). These automatically extracted ionospheric parameters were compared with those obtained manually and a good agreement was found. The developed tool will greatly expedite and standardize ionogram processing. Therefore, this new tool will facilitate exchange of information among many groups that operate ionosondes of the CADI type, and will be very helpful for space weather purposes. [Copyright &y& Elsevier]

Abstract: Carbidic austempered ductile iron is a family of ductile cast irons produced with carbides that are subsequently austempered to exhibit excellent wear resistance, which is a new type of austempered ductile iron recently introduced in the market. Heat treatment parameters affect the microstructure of the carbidic austempered ductile iron. Among heat treatment parameters, cooling rate from homogenization temperatures to salt bath temperatures is the most effective, and is often easy to be neglected. Therefore, the effect of cooling rate on the microstructure and mechanical properties of carbidic austempered ductile iron was investigated. The experimental results indicate that with the increase of the cooling rate, the size of acicular ferrite became fine acicular ferrite gradually, the austenite content was retained, the impact toughness decreases and the hardness of the samples increases. [Copyright &y& Elsevier]

• The state of psychology and quality of life of acne patients were influenced. • It is necessary to control weight and disease progression for acne patients. • The efficiencies of ALA-PDT for moderate to severe acne were 59.4 %–85.7 % at FU 1–3. • Progressive way of irradiation dose improved tolerance and reduced adverse reactions. To evaluate the state of psychology and quality of life of patients effected by acne and also the efficacy and safety of photodynamic therapy with topical 5-aminolevulinic acid (ALA-PDT) for moderate to severe acne patients. In the questionnaire part, a pre-designed form was filled out. The questionnaire was comprised of 2 sections related to acne including sociodemographic and disease information as well as Cardiff Acne Disability Index (CADI) and Self-Rating Anxiety Scale (SAS). In the trial part, the ALA-PDT was applied to moderate to severe acne patients. Fresh 5% ALA solution was topically applied to face or face & neck. After 1 h's incubation, a LED device was illuminated. A power density of 60−100 mW/cm2 was delivered for 20 min. All the patients finished 3–4 sessions of ALA-PDT at 7–10 days intervals. Non-invasive detections were taken for skin moisture, oil, and VISIA indexes. Adverse events were recorded during and after the treatment. A total of 247 acne patients finished questionnaires. Over 97 % patients were assessed as mild to severe impacts in CADI questionnaire and 37.6 % patients had various degrees of anxiety in SAS questionnaire. The higher the BMI was, the higher the CADI points were (G = 0.278, p = 0.005). The severity of acne was correlated with psychology and quality of life (CADI: G = 0.367, p = 0.000; SAS: G = 0.285, p = 0.003). A total of 116 patients with moderate or severe acne accepted ALA-PDT and completed at least 3 sessions (PDT3) or even PDT4. After 1 session of treatment (AT1) and AT2, the efficiencies of all patients were 5.2 % and 29.3 %. For patients with PDT3, the efficiencies at follow-up at 1st month after last session (FU1), FU2 and FU3 were 59.4 %, 66.7 % and 78.3 %, respectively. For patients with PDT4, the efficiencies at AT3 and FU1–3 were 51.3 %, 63.6 %, 76.5 % and 85.7 %, respectively. The efficacies of PDT4 patients showed an increasing trend from FU1 to FU3 (G = 0.480, p = 0.004). Acne lesions of mild to severe were correlated with the treatment efficacies (FU1: G = 0.354, p = 0.000; FU2: G = 0.474, p = 0.000; FU3: G = 0.397, p = 0.000). Nearly 15 % patients were followed up for 12 months and among them 52.9 % patients were able to maintain ≥90 % improvement rate. There were no statistically significant differences before and after treatment (p > 0.05) according to the skin moisture content, oil content, ultraviolet ray spots, brown spots, red areas, and purple textures measured. The adverse reactions of ALA-PDT, including local burning sensation, mild pain sensation, mild edema erythema, reactive acne, pigmentation, etc., were temporary and tolerable. In our study, 97.2 % patients were rated as impact in CADI questionnaire and 37.6 % patients had anxiety in SAS questionnaire. It is necessary to control weight and disease progression. The efficiencies of ALA-PDT for moderate and severe acne were 59.4%–85.7% at follow-ups of 1st, 2nd or 3rd month after last session. The adverse reactions of ALA-PDT were temporary and tolerable. [ABSTRACT FROM AUTHOR]

A new type heat treatment process comprising super-high temperature pretreatment and austempering treatment (S&A treatment) was used to process carbidic austempered ductile iron (CADI). The results showed that the netlike eutectic carbides were significantly reduced after super-high temperature pretreatment. Due to the increase in supercooling during super-high temperature pretreatment cooling, the inter-laminar spacing of pearlite was reduced from 300 nm to 100 nm. When the ductile iron with superfine pearlite was reheated, a large amount of Fe 3 C particles were retained inside the prior austenite grains. After austempering, a superfine ausferrite matrix with a length of 1–3 μm and a thickness of 50 nm was obtained. The main reason for this refinement is the increased number of nucleation-sites for the austenite grains and the retardation-effect of Cr on their growth. TEM results indicated that a possible orientation relationship between bainitic ferrite with a cubic lattice and precipitated Fe 3 C particles with a orthorhombic lattice is (01 1 ¯) α-Fe //(210) Fe3C , and their boundaries are coherent boundaries. The CADI obtained by S&A treatment has an impact toughness 120% higher than the traditional CADI without sacrificing hardness, and has excellent wear resistance under high wear load. Unlabelled Image • The impact toughness of CADI is significantly improved by super-high temperature pretreatment and austempering treatment. • The CADI obtained by S&A treatment has excellent wear resistance under high wear load. • With the rise of reheating temperature, the pearlite decreases gradually, and the precipitated particles are retained. • A superfine ausferrite matrix with a length of 1-3 μm and a thickness of 50 ± 10 nm is obtained. • The boundaries between bainitic ferrite and precipitated particles are coherent boundaries. [ABSTRACT FROM AUTHOR]