• 한국분말재료학회지
• /
• 제11권6호
• /
• pp.451-461
• /
• 2004

Dry sliding wear behavior of electro-pressure sintered Co-Fe and Co-Ni compacts was investigated. Pin-on-disk wear tests were performed on the sintered Co-Fe, Co-Ni disks against alumina $(Al_2O_3)$ and silica $(SiO_2)$ balls at various loads ranging from 3N to 12N. A constant sliding speed of 0.1m/sec was employed. Wear rate was calculated by dividing the weight loss of a specimen by the measured specific gravity and sliding dis-tance. Worn surfaces and cross-sections of the specimens were examined using an SEM and EDS to investigate wear mechanism of the compacts. The wear behavior of the compacts were discussed as a function of their com-position. Effects of mechancial properties of the compact as well as oxide layers formed on wearing surface on the wear were also discussed.

• 한국의류산업학회지
• /
• 제11권1호
• /
• pp.48-56
• /
• 2009

The purposes of this study were to segment knit wear consumers by their lifestyles and to examine knit wear purchase behavior among the lifestyle segments. The subjects of this study were female consumers who were residents in Seoul and metropolitan areas. The researchers distributed the questionnaires and the final sample of 357 was used for the data analysis. The statistical analysis methods used for the study were factor analysis, cluster analysis, ANOVA, Duncan test, and ${\chi}^2$-test. The results showed that the lifestyle factors had 6 dimensions: fashion, planned purchase, socially active, impulsive consumption, brand, and leisure/culture. These factors were categorized into four groups: brand oriented group, passive group, rational/social group, and fashion/impulsive consumption group. The results also showed that there were significant differences among the groups in regard to knit wear purchase criteria, knit wear image preferences, and other knit wear purchase behaviors. For example, brand oriented group considered design and brand name/fashion important as knit wear selection criteria, and the group preferred an elegance image and a modern image than did other groups.

• 대한기계학회논문집
• /
• 제12권6호
• /
• pp.1238-1245
• /
• 1988

본 연구에서는 단섬유가 첨가된 복합재료의 마찰 및 마멸특성에 대하여 보고 하고자 하며, 최근 공업용 고분자(engineering plastic)로 중오시되고 있는 PAI를 모 재로 하여 탄소섬유(graphite fiber), 유리섬유(glass fiber), TiO$_{2}$ 등이 첨가된 복합재료의 트라이볼로지(tribology) 특성에 대하여 고찰하고자 한다. 본 연구에서 사용된 복합재료에 포함된 단섬유들은 일정한 배열방향이 없이 마구잡이로 분포되어 있으며, 섬유특성에 따라 마멸메카니즘에 큰 차이가 있음을 본 연구 결과를 통하여 알 수 있다.

• Tribology and Lubricants
• /
• 제38권6호
• /
• pp.241-246
• /
• 2022

This paper presents the effects of cryogenic temperature on the wear behavior of 22MnB5 blank under cold stamping. After immersing the blank in liquid nitrogen (LN2) for 10 min, a strip drawing test was performed within 10 s. The hardness was measured using the Rockwell hardness test, which increased from 165 HV at 20℃ to 192 HV at cryogenic temperature. The strip drawing test with 22MnB5 blank and SKD61 tool steel shows that for the different wear mechanisms on the tool surface with respect to temperature; adhesive wear is dominant at 20℃, but abrasive wear is the main mechanism at cryogenic temperature. As the friction test is repeated, sticking gradually increases on the tool surface at 20℃, whereas the scratch increases at cryogenic temperature. For the friction behavior, the friction coefficient rapidly increases when adhesive wear occurs, and it occurs more frequently at 20℃. The results for nanoindentation near the worn blank surface indicate a difference of 1.3 GPa at 20℃ and 0.8 GPa at cryogenic temperature compared to the existing hardness, indicating increased deformation by friction at 20℃. This occurs because thermally activated energy available to move the dislocation decreases with decreasing temperature.

• 한국의상디자인학회지
• /
• 제20권3호
• /
• pp.1-14
• /
• 2018

This study examines female consumers' purchasing behavior of outdoor wear based on their leisure activities and life style using the questionnaire method. SPSSWIN was used for data analysis. The results are as follows: first, there is a significant difference in demographic characteristics of outdoor wear consumers depending on life style types. Second, outdoor wear purchasing behavior by lifestyle types showed no significant correlation between lifestyle types and the extent of interest in outdoor wear. Consumers valuing private leisure time are more engaged in searching for commercial information compared to other groups and a significant difference was seen in the standard for selecting products, functional materials, colors, and comfort depending on life style type. Third, there is no significant difference in demographic characteristics of outdoor wear consumers based on the extent of leisure activity. Fourth, there was significant correlation between the extent of leisure activity and interest in outdoor clothes. Therefore, this study shows that the life style of female consumers and the extent of leisure activity are significantly related to purchasing behavior. Hence this study can be effectively used by the outdoor wear industry to analyze characteristics of female consumers and plan and establish a suitable marketing strategy.

• 소성∙가공
• /
• 제20권7호
• /
• pp.479-484
• /
• 2011

Dry sliding wear behavior of AISI 52100 steel that has a pearlite or bainite microstructure was characterized to explore the effect of microstructure on the wear of the steel. Isothermal heat treatments were employed to obtain the different microstructures. Pin-on-disk type wear tests of the steel disk were performed at loads of 25~125N in air against an alumina ball. Sliding speed and wear distance used were 0.1m/sec and 300m, respectively. Worn surfaces, wear debris and cross-sections of the worn surfaces were examined with SEM to investigate the wear mechanism of the steel. Hardness of the steel was also evaluated. Wear rate of the steel was correlated with the hardness and the microstructure. On the whole, wear resistance increased with an increase in hardness. However, the pearlite microstructure showed superior wear resistance as compared to the bainite microstructure with a similar hardness. The effect of the microstructure on the wear rate was attributed to the morphological differences of the carbide in the microstructure, which was found to have a significant effect on strain hardening during the wear.

• 한국의상디자인학회지
• /
• 제10권3호
• /
• pp.37-46
• /
• 2008

The purposes of this article are segmenting consumers by brand attachment motives and discovering the differences among the segmented groups in relation to clothing involvement and clothing behavior (ready-to-wear satisfaction, brand loyalty, purchased items, and purchased places). The subjects of this study were male and female consumers, who were residents in Seoul, Korea. The data had been collected during May, 2007, and statistical analyses used for the study were factor analysis, cluster analysis, t-test, and chi-square test. The results showed that brand attachment motive is composed of two factors: brand personality/individuality expression and conformity/status improvement. Based on cluster analysis, there were two brand attachment motive groups: individuality expression and status improvement segments. T-test showed that brand attachment motive segments were significantly different in terms of clothing involvement and clothing behavior (ready-to-wear satisfaction, brand loyalty and purchased items). For example, the individuality expression group was more interested in clothing, was more satisfied with ready-to-wear clothing, had higher brand loyalty, and usually purchased casual wear. Meanwhile, the status improvement group had a higher perceived risk in clothing involvement, was less satisfied with ready-to-wear clothing, had a lower degree of brand loyalty, and preferred to purchase formal wear. The results implied that brand attachment motive is an important variable in market segmentation, in which specific marketing strategies should be implemented for each targeted consumers.

• Elastomers and Composites
• /
• 제58권3호
• /
• pp.103-111
• /
• 2023

The abrasion resistances of silica-filled styrene-butadiene rubber (SBR) compounds prepared with and without dicyclopentadiene resin (SBR-R and SBR-0, respectively) were studied using four different abrasion testers, namely cut and chip (CC), Lambourn, DIN, and laboratory abrasion tester (LAT100). The effect of the resin on the abrasion behavior was elucidated by analyzing the morphologies and size distributions of wear particles. All the wear particles had rough surfaces, but those obtained in the Lambourn abrasion test exhibited relatively smooth surfaces. The size distributions of the wear particles showed different trends depending on the abrasion tester and the rubber compound; however, most of the wear particles were larger than 1000 ㎛. The SBR-R sample showed a wide range of particle sizes (from 63 ㎛) in the LAT100 abrasion test and majority of the wear particles were 500-1000 ㎛, whereas the SBR-0 sample had the most distribution of larger than 1000 ㎛. The abrasion rates of SBR-0 sample were lower than those of the SBR-R sample for the CC and LAT100 abrasion tests, but the Lambourn abrasion test result showed the opposite trend. Addition of the resin influenced the abrasion behavior, however the effect varied depending on the type of abrasion tests.

• Tribology and Lubricants
• /
• 제13권1호
• /
• pp.21-27
• /
• 1997

The friction and wear behavior of undulated surfaces made of tin base babbit are examined experimentally at the low sliding speed with severe loading condition. Steel is used as counterface disk material under pin-on-disk type sliding condition. Undulated surfaces can improve the friction and wear properties under dry friction condition since undulated surfaces trap wear particles in their cavities and prohibit wear particles from agglomerating. However, under boundary lubrication condition, friction and wear properties of undulated surfaces are inferior to those of flat surfaces. It is shown that land width and the ratio of wear volume to cavity volume are the most important factors in friction behavior of undulated surfaces under dry friction condition, and there exists optimum land width minimizing friction and wear of undulated surfaces.

• 한국분말재료학회지
• /
• 제13권6호
• /
• pp.450-454
• /
• 2006

Wear of steel plate was measured during unlubricated sliding against TiC composites. These composites consist of round TiC grains and steel matrix. TiC grain itself exhibits low surface roughness and round shape, which does not bring its counterpart into severe damage from friction. In our work a classical experimental design was applied to find out a dominant factor in counterpart wear. The analysis of the data showed that only the applied load has a significant effect on the counterpart wear. Wear rate of counterpart increased non-linearly with applied load. Amount of wear was discrepant from expectation of being in proportion to the load by analogy with friction force. Our experimental result from treating matrix variously revealed bimodal wear behavior between the composites and counterpart where a mode seems to result from the special lubricant characteristic of TiC grains, and the other is caused by metal-to-metal contact. The two wear mechanisms were discussed.