Emre Tascioglu, Hamaid Mahmood Khan, Yusuf Kaynak, Mert Coşkun, Gurkan Tarakci and Ebubekir Koç
The present study aims to investigate the effect of finish machining and aging processes on the surface integrity of the selective laser melted (SLM) maraging steel samples and…
Abstract
Purpose
The present study aims to investigate the effect of finish machining and aging processes on the surface integrity of the selective laser melted (SLM) maraging steel samples and compared them with those obtained conventionally.
Design/methodology/approach
Finish machining and aging were applied on the SLM and wrought maraging samples to investigate and compare their microstructural and mechanical properties such as surface roughness, microhardness and wear resistance.
Findings
After applying aging and finish machining treatments, the surface roughness <1 µm, microhardness (542Hv) and wear resistance (COF 0.578) of SLM samples were similar to their wrought counterparts. Compared to finish machining, the effect of aging was more significant on the microhardness and the wear resistance, regardless of sample type.
Originality/value
The knowledge of post-processing is essential to enhance the functional performance of the SLM samples. Aging and finish machining were applied for the first time to evaluate the surface integrity of the SLM prepared maraging steel and compared it with the wrought samples.
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Onur Ertuğrul, Zafer Çağatay Öter, Mustafa Safa Yılmaz, Ezgi Şahin, Mert Coşkun, Gürkan Tarakçı and Ebubekir Koç
The purpose of this paper is to evaluate the effect of post process combinations, e.g. hot isostatic pressing (HIP) only, HIP + T6 heat treatments, and T6 only, with different…
Abstract
Purpose
The purpose of this paper is to evaluate the effect of post process combinations, e.g. hot isostatic pressing (HIP) only, HIP + T6 heat treatments, and T6 only, with different aging time, on surface properties, microstructure and mechanical properties of stress-relieved AlSi10Mg parts produced by direct laser metal sintering.
Design/methodology/approach
HIP process and HIP + T6 heat treatments were applied to as stress-relieved direct laser metal sintered (DMLS) AlSi10Mg parts. Aging times of 4 and 12 h are selected to examine the optimum duration. To analyze the advantages of HIP process, a T6 heat treatment with 4 h of aging was also applied. Densities, open porosities and roughness values of as stress-relieved, HIPed, HIP + T6, and T6-only samples were measured. The samples were characterized by OM and SEM together with EDX analysis. An image analysis study was made to evaluate the inner pore structure, thereby to understand the mechanical behavior.
Findings
HIP process does not cause a significant change in surface porosity; yet it has a positive influence on inner porosity. HIP process results in a microstructure of the aluminum matrix surrounded by a network of micron and nano size Si particles. Additional heat treatment results in larger particles and precipitation. After HIPing, ductility increases but strength decreases. Samples aged 4 h present improved yield and tensile strength but decreased elongation, yet samples aged for 12 h reach a combination of optimum strength and ductility. The lower level of tensile strength and ductility in T6-only condition indicates that HIP process plays a crucial role in elimination of the porosity thus improves the effectiveness of subsequent heat treatment.
Originality/value
The study investigates the effect of post-process conditions and optimizes the aging time of the T6 heat treatment after HIP process in order to obtain improved mechanical properties. The stress-relieved state was chosen as the reference to prevent distortion during HIPing or heat treatment.
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Ayşen Coşkun and Raife Meltem Yetkin Özbük
The purpose of this study is to segment young millennials in an emerging economy based on their environmental attitudes and purchase intentions. The study also attempts to…
Abstract
Purpose
The purpose of this study is to segment young millennials in an emerging economy based on their environmental attitudes and purchase intentions. The study also attempts to describe the segments and highlight their differences in terms of happiness, frugality, environmental locus of control, and environmental knowledge.
Design/methodology/approach
The study sample consisted of 227 Turkish undergraduate students. A two-step cluster analysis was performed on environmental attitudes and purchase intentions scores. The differences among the clusters were then examined according to happiness, frugality, environmental locus of control, and environmental knowledge variables.
Findings
A two-step cluster analysis identified three clusters, namely, “non-greens”, “reluctant greens” and “true greens”, all of whom differed in terms of environmental attitudes and purchase intentions. Non-greens (n = 16) and true greens (n = 121) yielded the lowest and the highest scores for environmental attitudes and purchase intentions, respectively. Three clusters also differed significantly in terms of frugality. Environmental knowledge levels of non-greens differed from those of reluctant greens and true greens. There is no significant difference regarding happiness and environmental locus of control among clusters.
Practical implications
Local and international companies interested in marketing green products to young millennials in emerging economies may enhance their understanding of non-green and green young millennials in the target markets and differentiate their marketing strategies for each segment.
Originality/value
Given the need for a better understanding of young millennials’ environmental behavior in an emerging economy, the current study contributes to the literature by segmenting young Turkish millennials based on their environmental attitudes and purchase intentions, further describing the consumer segments with different variables such as happiness, frugality, environmental locus of control and environmental knowledge.
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Ferit Ölçer and Ömer Faruk Coşkun
The purpose of this study is to determine the relationships between organizational justice, organizational silence and organizational creativity and to examine the mediating role…
Abstract
Purpose
The purpose of this study is to determine the relationships between organizational justice, organizational silence and organizational creativity and to examine the mediating role of organizational silence in the effect of organizational justice on organizational creativity.
Design/methodology/approach
Research data were collected using a face-to-face survey method applied to employees in the automotive industry in Turkey. The research model and hypotheses were tested by structural equation modeling.
Findings
Research results indicate that organizational justice positively affects organizational silence, organizational creativity is positively affected by organizational justice and organizational silence positively affects organizational creativity. Besides, according to the results, organizational silence has a partial mediating role in the effect of organizational justice on organizational creativity.
Originality/value
Although the relationships between organizational justice, organizational silence and organizational creativity were examined in previous studies in the literature, the role of organizational silence in the relationship between organizational justice and organizational creativity was not investigated. Besides, although previous studies examined the mediating role of variables that are thought to have a positive effect on the organization between organizational justice and organizational creativity, they did not study the role of a variable of organizational silence, which is considered negative. For these reasons, this study is predicted to differentiate the perspective in the literature and fills a gap in the literature.
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Jafar Hayaty Nejad, Ali Mohamadi Sani and Mohammad Hojjatoleslamy
– The purpose of this paper was to determine the effects of the spinach extract and kiwi flavor on the physicochemical and organoleptic properties of yogurt.
Abstract
Purpose
The purpose of this paper was to determine the effects of the spinach extract and kiwi flavor on the physicochemical and organoleptic properties of yogurt.
Design/methodology/approach
A total of 48 yogurt samples including yogurts flavored with kiwi flavor (1, 2 and 4 percent) and colored with spinach extract (1.25, 2.5 and 4 percent) and a control yogurt (no kiwi flavor or spinach extract) were evaluated for chemical, physical and sensory properties during 21 days of storage. Data were analyzed by ANOVA using statistical analysis system.
Findings
Statistically significant differences (p<0.05) were found between the control and kiwi-spinach yogurts in terms of viscosity and syneresis. The addition of the spinach extract to yogurt resulted in an increase in the syneresis, and a decrease in the viscosity. During the storage, the values of the titratable acidity, viscosity and syneresis of yogurt samples increased, while pH decreased significantly (p<0.05). Yogurt enriched with 4 percent spinach extract and 4 percent kiwi flavor was more acceptable than the other samples, and high scored with respect to overall acceptability by panelists.
Originality/value
No research had been done to formulate and compare the sensory and physicochemical properties of kiwi-spinach yogurt in Iran.