Tham khảo tài liệu 'asm metals handbook - desk edition (asm_ 1998) episode 2', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | faces and two-dimensional projections of the liquidus and solidus surfaces along with a series of two-dimensional horizontal sections isotherms and vertical sections isopleths through the solid diagram. Vertical sections are often taken through one corner one component and a congruently melting binary compound that appears on the opposite face when such a plot can be read like any other true binary diagram it is called a quasi-binary section. One possibility of such a section is illustrated by line 1-2 in the isothermal section shown in Fig. 10. A vertical section between a congruently melting binary compound on one face and one on a different face might also form a quasibinary section see line 2-3 . Fig. 10 Isothermal section of a ternary diagram with phase boundaries deleted for simplification All other vertical sections are not true binary diagrams and the term pseudobinary is applied to them. A common pseudobinary section is one where the percentage of one of the components is held constant the section is parallel to one of the faces as shown by line 4-5 in Fig. 10. Another is one where the ratio of two constituents is held constant and the amount of the third is varied from 0 to 100 line 1-5 . Isothermal Sections. Composition values in the triangular isothermal sections are read from a triangular grid consisting of three sets of lines parallel to the faces and placed at regular composition intervals see Fig. 11 . Normally the point of the triangle is placed at the top of the illustration component A is placed at the bottom left B at the bottom right and C at the top. The amount of constituent A is normally indicated from point C to point A the amount of constituent B from point A to point B and the amount of constituent C from point B to point C. This scale arrangement is often modified when only a corner area of the diagram is shown. Fig. 11 Triangular composition grid for isothermal sections X is the composition of each constituent in mole fraction or .
