Characterization of the structure and magnetic properties of Fe49Co2V made by the powder metal injection molding route

The semi-hard magnetic alloy Fe49Co2V is widely used in electronics and automation. Many of these parts are complex ones which can be produced with significant advantages by the PIM technology. In this work the feedstock was prepared by mixing the starting powder with a "Solvent System" binder. The injected green samples of toroidal shape were first subjected to solvent debinding. Secondary thermal debinding at optimized temperatures and sintering in the temperature range 1370-1460°C was performed in hydrogen in an Elnik System furnace. Magnetic properties were measured from hysteresis graphs for soft magnetic materials and the main properties such as such as remanent induction Br coercive force Hcb, saturation induction Bs and relative permeability μr were determined. The hysteresis curves obtained were correlated to the microstructures formed during sintering. The results obtained were compared with the data for other technologies of preparing Fe-Co-V from available literature. It is shown that the PIM samples reach magnetic property values comparable to those obtained by conventional methods

Parallel analysis of axial pressing, casting and PIM as routes for production of alnico8

Samples of Alnico8 were prepared from the same starting powder by pressing, casting and powder injection moulding (PIM), respectively, and characterized by SEM and thermal analysis-DTA/TGA. Optimization of the sintering process was done for reaching the optimum of the energy product (BH)max for each type of samples. During sintering of the PIM specimens, special attention was paid to lowering the contents of residual C and O in the Alnico alloys since these interstitials affect the main magnetic properties. PIM samples were prepared using a feedstock composed of Alnico powder and a Catamold® (BASF) binder. For analysis of the thermal debinding of PIM samples, sintering was done in a dilatometer with coupled mass spectrometer. Shape anisotropy was induced by thermo magnetic treatment of all samples. Subsequently the main magnetic properties were measured and compared mutually and with the best literature results. It was clearly shown from the results obtained that PIM samples can attain the properties of Alnico samples made by classical routes. The microstructure of the sintered PIM samples was analyzed by SEM

Patient exposure dose in interventional cardiology per clinical and technical complexity levels. Part 1: results of the VERIDIC project

Background: Patients can be exposed to high skin doses during complex interventional cardiology (IC) procedures. Purpose: To identify which clinical and technical parameters affect patient exposure and peak skin dose (PSD) and to establish dose reference levels (DRL) per clinical complexity level in IC procedures. Material and Methods: Validation and Estimation of Radiation skin Dose in Interventional Cardiology (VERIDIC) project analyzed prospectively collected patient data from eight European countries and 12 hospitals where percutaneous coronary intervention (PCI), chronic total occlusion PCI (CTO), and transcatheter aortic valve implantation (TAVI) procedures were performed. A total of 62 clinical complexity parameters and 31 technical parameters were collected, univariate regressions were performed to identify those parameters affecting patient exposure and define DRL accordingly. Results: Patient exposure as well as clinical and technical parameters were collected for a total of 534 PCI, 219 CTO, and 209 TAVI. For PCI procedures, body mass index (BMI), number of stents ≥2, and total stent length >28 mm were the most prominent clinical parameters, which increased the PSD value. For CTO, these were total stent length >57 mm, BMI, and previous anterograde or retrograde technique that failed in the same session. For TAVI, these were male sex, BMI, and number of diseased vessels. DRL values for Kerma-area product (PKA), air kerma at patient entrance reference point (Ka,r), fluoroscopy time (FT), and PSD were stratified, respectively, for 14 clinical parameters in PCI, 10 in CTO, and four in TAVI. Conclusion: Prior knowledge of the key factors influencing the PSD will help optimize patient radiation protection in IC

Patient exposure dose in interventional cardiology per clinical and technical complexity levels. Part 1: results of the VERIDIC project.

Patients can be exposed to high skin doses during complex interventional cardiology (IC) procedures. To identify which clinical and technical parameters affect patient exposure and peak skin dose (PSD) and to establish dose reference levels (DRL) per clinical complexity level in IC procedures. Validation and Estimation of Radiation skin Dose in Interventional Cardiology (VERIDIC) project analyzed prospectively collected patient data from eight European countries and 12 hospitals where percutaneous coronary intervention (PCI), chronic total occlusion PCI (CTO), and transcatheter aortic valve implantation (TAVI) procedures were performed. A total of 62 clinical complexity parameters and 31 technical parameters were collected, univariate regressions were performed to identify those parameters affecting patient exposure and define DRL accordingly. Patient exposure as well as clinical and technical parameters were collected for a total of 534 PCI, 219 CTO, and 209 TAVI. For PCI procedures, body mass index (BMI), number of stents ≥2, and total stent length >28 mm were the most prominent clinical parameters, which increased the PSD value. For CTO, these were total stent length >57 mm, BMI, and previous anterograde or retrograde technique that failed in the same session. For TAVI, these were male sex, BMI, and number of diseased vessels. DRL values for Kerma-area product (P <sub>KA</sub> ), air kerma at patient entrance reference point (K <sub>a,r</sub> ), fluoroscopy time (FT), and PSD were stratified, respectively, for 14 clinical parameters in PCI, 10 in CTO, and four in TAVI. Prior knowledge of the key factors influencing the PSD will help optimize patient radiation protection in IC

Penetration, Overlay, Governmentality: The Evolving Role of NATO in the Western Balkan Security Dynamics

According to the Regional Complex Security Theory (RSCT) external involvement in regional security can take either the form of penetration or overlay. We theorise governmentality as the third form of external involvement aimed to responsibilise regions in order to govern them indirectly and at a distance. We illustrate our argument in a study of NATO's role in the Western Balkans since the dissolution of Yugoslavia. In particular, we posit that the predominant role of NATO in the region has evolved over time from penetration in the 1990s, through overlay in the early 2000s, to today's governmentality

Establishing a priori and a posteriori predictive models to assess patients' peak skin dose in interventional cardiology. Part 2: results of the VERIDIC project.

Optimizing patient exposure in interventional cardiology is key to avoid skin injuries. To establish predictive models of peak skin dose (PSD) during percutaneous coronary intervention (PCI), chronic total occlusion percutaneous coronary intervention (CTO), and transcatheter aortic valve implantation (TAVI) procedures. A total of 534 PCI, 219 CTO, and 209 TAVI were collected from 12 hospitals in eight European countries. Independent associations between PSD and clinical and technical dose determinants were examined for those procedures using multivariate statistical analysis. A priori and a posteriori predictive models were built using stepwise multiple linear regressions. A fourfold cross-validation was performed, and models' performance was evaluated using the root mean square error (RMSE), mean absolute percentage error (MAPE), coefficient of determination (R²), and linear correlation coefficient (r). Multivariate analysis proved technical parameters to overweight clinical complexity indices with PSD mainly affected by fluoroscopy time, tube voltage, tube current, distance to detector, and tube angulation for PCI. For CTO, these were body mass index, tube voltage, and fluoroscopy contribution. For TAVI, these parameters were sex, fluoroscopy time, tube voltage, and cine acquisitions. When benchmarking the predictive models, the correlation coefficients were r = 0.45 for the a priori model and r = 0.89 for the a posteriori model for PCI. These were 0.44 and 0.67, respectively, for the CTO a priori and a posteriori models, and 0.58 and 0.74, respectively, for the TAVI a priori and a posteriori models. A priori predictive models can help operators estimate the PSD before performing the intervention while a posteriori models are more accurate estimates and can be useful in the absence of skin dose mapping solutions