Z phase precipitation in martensitic 12CrMoVNb steels

Precipitation of Z phase contributes significantly to degradation of creep properties of 12CrMoVNb steels because its precipitation is accompanied by dissolution offinely dispersed nitrides and carbonitrides of M2X and/or MX type. The orientation relationship between Z phase and the ferritic matrix was determined as: $(001)_{\rm z}// (001)_{\alpha}$, $[010]_{\rm z} // [010]_{\alpha}$. Prolonged thcrmal/creep exposure is accompanied by recrystallisation of the matrix and this orientation relationship is destroyed. Nevertheless Z phase particles preserve the form of thin plates. Z phase is a nitride which is rich in vanadium, niobium and chromium and its composition depends on both the temperature of precipitation and the initial chemical composition of steels. The composition of Z phase does not change during long term exposure at the original precipitation temperature. A relationship between the composition of Z phase and its temperature of formation may be able to be used as a temperature exposure indicator of steels. However it is also necessary to know the Z phase composition for a given cast of material

Microstructural aspects of the creep ductility and fracture of unstabilised austenitic CrNiMo steels

26.00; Translated from Czech. (Hutn. Listy 1988 v. 43(9) p. 633-640)Available from British Library Document Supply Centre- DSC:9023.19(VR-Trans--4144)T / BLDSC - British Library Document Supply CentreSIGLEGBUnited Kingdo

Needle shaped intergranular precipitates in 08Kh18N10T steel (08Cr10Ni0.5Ti)

Translated from Czech. (Kovove Mater. 1988 v. 26(3) p. 364-380)SIGLEAvailable from British Library Document Supply Centre- DSC:9023.19(VR-Trans--3940)T / BLDSC - British Library Document Supply CentreGBUnited Kingdo

Statistical normalisation of M23C6 carbides precipitation kinetics, changes in chromium concentration in their vicinity and electrochemical charateristic of EPR tests

International audienc

Antibodies against Pneumococcal Capsular Polysaccharides and Natural Anti-Galactosyl (Alpha-Gal) in Patients with Humoral Immunodeficiencies

Humoral deficiencies represent a broad group of disorders. The aim of the study was to compare the levels of antibodies against pneumococcal capsular polysaccharides (anti-PCP) and natural anti-galactosyl (anti-Gal) antibodies in (1) patients with chronic lymphocytic leukaemia (CLL), (2) patients with common variable immunodeficiency (CVID), and (3) a healthy population and to explore their diagnostic and prognostic potential. Serum immunoglobulin levels and levels of anti-Gal IgG, IgA, and IgM and anti-PCP IgG and IgG2 were determined in 59 CLL patients, 30 CVID patients, and 67 healthy controls. Levels of IgG, IgA, IgM, anti-Gal IgA, anti-Gal IgM, and anti-PCP IgA were lower in CLL and CVID patients than in healthy controls (p value for all parameters < 0.0001). Decrease in the levels of IgA, IgM, anti-Gal IgA, and anti-PCP IgA was less pronounced in the CLL group than in the CVID group. IgA decline, anti-Gal IgA, anti-PCP IgA, and anti-PCP IgG2 were negatively correlated with CLL stage. We devise the evaluation of anti-Gal antibodies to be a routine test in humoral immunodeficiency diagnostics, even in cases of immunoglobulin substitution therapy. Significant reductions, mainly in anti-Gal IgA, IgM, and anti-PCP IgA levels, may have prognostic importance in CLL patients

New types of lead-free solders and their properties

The aim of this work is an experimental study of lead-free solders. Ternary and binary alloys with different ratios of individual elements Ag, Al, Bi, Cu, In, Mg, Sb, Sn and Zn were prepared experimentally. The study of low-fusing solder alloys was performed with the aspect of observing their selected physical, chemical, structural and technological properties. The following characteristics were studied: temperatures and enthalpies of phase transformations (DTA, TG, DSC) of individual solders at the rates of re-heating and cooling of specimens of about 4 degrees C/min, macro-and micro-structural analysis (optical metallography), micro-hardness, chemical analysis: ICP-AES, optical emission spectrometry (OES), X-ray micro-analysis of individual phases in the structure of solders (WDX, EDX), measurement of density and electrical resistivity of selected solders in dependence on the temperature, test of wettability with or without use of fluxes, measurement of corrosion properties

New types of lead-free solders and their properties

The aim of this work is an experimental study of lead-free solders. Ternary and binary alloys with different ratios of individual elements Ag, Al, Bi, Cu, In, Mg, Sb, Sn and Zn were prepared experimentally. The study of low-fusing solder alloys was performed with the aspect of observing their selected physical, chemical, structural and technological properties. The following characteristics were studied: temperatures and enthalpies of phase transformations (DTA, TG, DSC) of individual solders at the rates of re-heating and cooling of specimens of about 4 degrees C/min, macro-and micro-structural analysis (optical metallography), micro-hardness, chemical analysis: ICP-AES, optical emission spectrometry (OES), X-ray micro-analysis of individual phases in the structure of solders (WDX, EDX), measurement of density and electrical resistivity of selected solders in dependence on the temperature, test of wettability with or without use of fluxes, measurement of corrosion properties