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T. Ebner et al.
tungsten in the binder on the formation of these alloys by contacting Co(W) testing
material with liquid zinc at 600–750 °C for 0.5–8 h.
Experimental
To investigate the formation of intermetallic phases in the Co(W)–Zn system, tungsten containing Co testing material was contacted with liquid zinc at a certain temperature for various durations. Figure 2 depicts electron images, element distributions,
and chemical analyses of the Co(W) staring materials (M1, M2 and M3) by scanning
electron microscopy with energy dispersive spectroscopy (SEM/EDS). The measurements were performed with a JEOL JSM-IT300 SEM. The EDS analyses reveal W
contents of 3.77 wt% in M2 and 4.01 wt% in M3. Since the testing material M1 only
consists of cobalt, no mapping is given in this case. The solid metals were sliced
into cubes with an edge length of 10 mm, which served as starting materials for this
study.
The application of the statistical software Modde 12 assisted the creation of a
design of experiments by a full factorial model according to the response surface
methodology (RSM) and the generation of reliable data from the tests, which were
conducted at different temperatures (600, 675, 750 °C), durations (0.5, 4.25, 8 h),
and Co(W) testing materials (M1, M2, M3). The sliced Co(W) cubes were placed in
a quartz crucible. Subsequently, 99.9999% pure zinc, heated to the target temperature was casted on the cube. The average ratio of Zn:Co accounted for 116:1, which
allows an observation of the intermetallic Co–Zn layer formation far off the chemical
equilibrium, since an excess of zinc is available for the reaction with cobalt. Afterwards, the crucibles were held for a certain duration in a nitrogen flushed resistance
furnace at the desired temperature, followed by a cooling at ambient temperature and
a metallographic preparation to enable the analyses by SEM/EDS and light optical
microscopy (LOM) via the application of a Zeiss Axio Imager M1M. Figure 3 disFig. 2 SEM/EDS analyses of the three different testing materials (M1, M2, and M3)
T. Ebner et al.
tungsten in the binder on the formation of these alloys by contacting Co(W) testing
material with liquid zinc at 600–750 °C for 0.5–8 h.
Experimental
To investigate the formation of intermetallic phases in the Co(W)–Zn system, tungsten containing Co testing material was contacted with liquid zinc at a certain temperature for various durations. Figure 2 depicts electron images, element distributions,
and chemical analyses of the Co(W) staring materials (M1, M2 and M3) by scanning
electron microscopy with energy dispersive spectroscopy (SEM/EDS). The measurements were performed with a JEOL JSM-IT300 SEM. The EDS analyses reveal W
contents of 3.77 wt% in M2 and 4.01 wt% in M3. Since the testing material M1 only
consists of cobalt, no mapping is given in this case. The solid metals were sliced
into cubes with an edge length of 10 mm, which served as starting materials for this
study.
The application of the statistical software Modde 12 assisted the creation of a
design of experiments by a full factorial model according to the response surface
methodology (RSM) and the generation of reliable data from the tests, which were
conducted at different temperatures (600, 675, 750 °C), durations (0.5, 4.25, 8 h),
and Co(W) testing materials (M1, M2, M3). The sliced Co(W) cubes were placed in
a quartz crucible. Subsequently, 99.9999% pure zinc, heated to the target temperature was casted on the cube. The average ratio of Zn:Co accounted for 116:1, which
allows an observation of the intermetallic Co–Zn layer formation far off the chemical
equilibrium, since an excess of zinc is available for the reaction with cobalt. Afterwards, the crucibles were held for a certain duration in a nitrogen flushed resistance
furnace at the desired temperature, followed by a cooling at ambient temperature and
a metallographic preparation to enable the analyses by SEM/EDS and light optical
microscopy (LOM) via the application of a Zeiss Axio Imager M1M. Figure 3 disFig. 2 SEM/EDS analyses of the three different testing materials (M1, M2, and M3)