Variation of Internal Friction with Magnetization in Nickel

The internal friction Q^ of nickel annealed at 1000℃ for 10hr was measured in a magnetic field by the electrostatic driving method. The results obtained are as follows : (1) With decreasing magnetic field H from a magnetically saturated state, Q^ increases from about H=30 Oe and shows a maximum at H=15 Oe. (2) The magnetic hysteresis loss Q^_h was separated from the whole Q^ through measurement of the dynamic stress with an interference comparameter. (3) When Q^_h is expressed as a function of magentization I/I_s, Q^_h shows a maximum at I/I_s=0.6 ; it becomes smaller with increasing driving frequency f and vanishes at f=5.8 kHz

Thermal Expansion Coefficient of Fe-Ni(fcc) Alloys

The thermal expansion coefficient, α, was measured over the range from 800℃ to room temperature for Fe-Ni(fcc) alloys. The results obtained are as follows : (1) On the temperature vs. α curve, a peak appears at the Curie temperature, T_c, in the composition range above 42% of Ni but none in the range of 42-30% of Ni. (2) T_c of the alloys with more than 42% of Ni is present in the γ phase at a temperature higher than the upper limit for (α+γ) mixture phase in the equilibrium diagram. (3) the value of α_P obtained from α by climinating the magnetic contribution shows a minimum in the Invar range as in the case of α. This may suggest that the interatomic cohesive force must be considered in addition to the magnetic effect in making clear the origin of Invar property

The Effect of Carbon Addition on the Magnetic Shunt Properties of M.S.O. Alloy

The magnetic shunt properties of a kind of M.S.O. Alloy (31%Ni, 8.5%Cr and rest Fe) containing C from 0.019 to 0.150% were studied. The magnetization curves at 0°to 40℃ were measured by the ballistic method. The dimension of specimen was 0.4 cm in diameter, 3.1 cm in length, and so the demagnetization factor N was 0.30. The experimental results on magnetic shunt properties are summarised as follows : (1) With increasing C addition, the permeability decreases at first and then increases slightly through a feeble minimum. It is assumed that the former decreasing is due to the impurity of C and the latter increasing due to the formation of Fe_6Cr_C_6 which is speculated by the microscopic. texture and the calculation. (2) The temperature coefficient of permeability becomes larger with increasing C addition, and its linearity becomes worse

Facial trauma with life-threatening bleeding treated by andexanet alfa administration: A case report

Recently, anticoagulant reversal has become a treatment option for life-threatening bleeding, especially in intracranial hemorrhage. Although evidence of the beneficial efficacy of andexanet alfa accumulates in cases of intracranial hemorrhage, little is known about its effectiveness in head injuries without intracranial hemorrhage. We present the case of an 87-year-old man who suffered a stroke 1 year previously and had been taking apixaban since then, who was brought to the emergency department with facial trauma due to a fall. Upon arrival at the hospital, the patient was conscious, and his vital signs were normal; however, physical examination revealed epistaxis, and plain head computed tomography (CT) showed multiple facial fractures without intracranial hemorrhage. As epistaxis was challenging to control, upper airway obstruction developed. His percutaneous oxygen saturation (SpO₂) decreased rapidly, and he underwent tracheal intubation. Contrast-enhanced head CT revealed at least two extravasations, near the anterior wall of the right maxillary sinus and from the nasal canal to the nasopharynx area. However, embolization using interventional radiology was deemed difficult. Because the bleeding did not stop, we determined the bleeding was life-threatening and uncontrollable. Therefore, we infused andexanet alfa to stop the bleeding. After infusion, hemostasis was confirmed. This case suggests the effectiveness of andexanet alfa in cases of facial trauma and extracranial bleeding difficult to stop, resulting in favorable outcomes and hemostatic effects

ΔE Effect of Nickel

The change in Young\u27s modulus E by the magnetic field H, the ΔE effect, of Ni has been investigated in as-cold-worked and annealed states with an electrostatic driving method. The dynamic stress was measured with an interference comparametor. The results obtained are as follows : (1) The saturation value of the ΔE effect (ΔE/E_0)_s is 2.1% in the as-cold-worked state and increases rapidly with annealing at 400℃ and then gradually approaches a constant value after a complicated change. (2) The E-H curve measured with a low resonance frequency shows a minimum in the weak magnetic field. The minimum decreases with increasing resonance frequency and finally vanishes. (3) The frequency dependence of the ΔE effect is most remarkable at the magnetization I/I_s=0.7～0.6. (4) The stress dependence of E at δ=3.4 and 49.0 k dyne/cm^2 is not remarkable in any magnetized state. (5) The three types of the ΔE curve may be qualitatively explained on the assumption that the dynamic ΔE effect is a combined one of the variation in magnetostriction and the vibration

Young\u27s Modulus, Shear Modulus and Compressibility of Fe-Ni(fcc) Alloys

The flexural and torsional resonance frequencies were measured by electrostatic driving method in vacuum at a magnetic field of H=1200 Oe for the same specimens of Fe-Ni(fcc) alloys. The results obtained are as follows : (1) Young\u27s modulus, shear modulus and compressibility in a paramagnetic state E_p, G_p and κ_p, were separated from the experimental values in a ferromagnetic state, respectively. E_p G_p and κ_p show anomalies. The former two show a maximum and the latter a minimum in the Invar region, which may suggest that there exists an anomaly in the interatomic binding force in the Invar alloys. (2) In the Invar region, the temperature coefficient of Young\u27s modulus (dE/dT)/E, becomes highest and the thermal expansion coefficient lowest. (3) The Elinvar property (that is, dE/dT)/E=0) appears at 44% Ni