(FeMnNi)84(AlTi)16 high‑entropy alloy: correlation of microstructure, strengthening mechanisms and hardness at various conditions (As‑Cast, solution treated, aged)

A (FeMnNi)84(AlTi)16 high-entropy alloy was produced by vacuum arc melting successfully. The microstructure of the as-cast state showed the existence of two FCC phases along with potential precipitates. The solution treatment response of the alloy for 2 h at 1150 °C and the effect of aging time at 750 °C in the microstructure and microhardness were also evaluated. It was observed that the solution treatment parameters were insufficiently low to dissolve the as-cast precipitates into the matrix. The double FCC matrix identified may be correlated with a solidification range and insufficient diffusion during the solidification process. The maximum hardness at 90 min aging time can be mainly attributed to the precipitation shearing mechanism in both matrix areas. The lower hardness value reported at 160 h aging time was estimated that it is derived by the change of the main strengthening mechanism from shearing to Orowan. The island-like precipitates that depleted Ti element from the Ni-rich intergranular area may be identified as a Ni2AlTi Heusler phase

Mixed (composite) glandular-endocrine cell carcinoma of the gallbladder

Background A mixed pattern of glandular and neuroendocrine elements is rare in tumours at any site within the gastrointestinal tract but particularly so in the gallbladder. Case outline A 72‐year‐old woman presented with abdominal pain and jaundice and was found to have a large mass in the fundus of the gallbladder.The mass was radically excised to include a wedge of liver and the hepatoduodenal lymph nodes. Histopathological examination of the resected gallbladder showed an invasive tumour composed of both adenocarcinoma and endocrine cell carcinoma, with apparent transitions between them. The patient received no further treatment and died two months later. Discussion There are 14 previous case reports of mixed adeno/endocrine carcinoma of the gallbladder. Histochemical similarities between the two neoplastic components of the present tumour would support their origin from a common precursor cell, but the alternative hypothesis of coincidental neoplastic change in two different cell types cannot be excluded