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In this work, alloys of Nd(Fe1-xCox)10.5M1.5 (M=Mo and V) were prepared via arc melting and heat treatment. The nitrides of these alloys were synthesized using a gas-solid state reaction method. The influence of Co substitution for Fe in NdFe10.5Mo1.5 and NdFe10.5V1.5 alloys and their nitrides were investigated. It was found that the lattice parameters a, c, and unit cell volume V decrease with increasing Co content x for Nd(Fe1-xCox)10.5Mo1.5. As compared to their parent alloys, the lattice parameters and unit cells volume increase after nitrogenation, which gives rise to higher Curie temperature, magnetization and magnetocrystalline anisotropy field for nitrides. A small amount of Co substitution for Fe (x≤0.3) can enhance the magnetic properties including Curie temperature, saturation magnetization and magnetocrystalline anisotropy field of the alloys and their nitrides, while higher concentration of Co (x>0.3) will deteriorates these magnetic properties, especially for the nitrides, due to the modification of the band structure by Co atom. As a result, Nd(Fe1-xCox)10.5Mo1.5Ny and Nd(Fe1-xCox)10.5V1.5Ny with x≤0.2 become promising candidates for permanent magnet applications. A coercivity of 4.6 kOe and maximum energy product BHmax of 20 MGOe were achieved for NdFe9.45Co1.05Mo1.5Nx.

In the past decade, Mn rich Ni-Mn based alloys have attained considerable attention due to their abundant physics and potential application as multifunctional materials. In this paper, polycrystalline Ni50Mn38−xPdxSn12 (x = 0, 2, 4, 6) Heusler alloys have been prepared, and the martensitic phase transformation (MPT) together with the shape memory effect and the magnetocaloric effect has been investigated. The experimental result indicates that the MPT evidently shifts to a lower temperature with increase of Pd substitution for Mn atoms, which can be attributed to the weakness of the hybridization between the Ni atom and excess Mn on the Sn site rather than the electron concentration. The physics properties study focused on the sample of Ni50Mn34Pd4Sn12 shows a good two-way shape memory behavior, and the maximum value of strain Δ L/L reaches about 0.13% during the MPT. The small of both entropy change Δ ST and magnetostrain can be ascribed to the inconspicuous influence of magnetic field induced MPT.

We characterize spall damage in shock-recovered ultrapure Al with metallography and x-ray tomography. The measured damage profiles in ultrapure Al induced by planar impact at different shock strengths, can be described with a Gaussian function, and showed dependence on shock strengths. Optical metallography is reasonably accurate for damage profile measurements, and agrees within 10–25% with x-ray tomography. Full tomography analysis showed that void size distributions followed a power law with an exponent of γ = 1.5 ± 2.0, which is likely due to void nucleation and growth, and the exponent is considerably smaller than the predictions from percolation models.