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The purpose of this study is to investigate the effect of ferrite on hydrogen embrittlement (HE) of the 17-4PH stainless steels.

The effects of ferrite on HE of the 17-4PH stainless steels were investigated by observing microstructure and conducting slow-strain-rate tensile tests and hydrogen permeability tests.

The microstructure of the ferrite-bearing sample is lath martensite and banded ferrite, and the ferrite-free sample is lath martensite. After hydrogen charging, the plasticity of the two steels is significantly reduced, along with the tensile strength of the ferrite-free sample. The HE susceptibility of the ferrite-bearing sample is significantly lower than the ferrite-free steel, and the primary fracture modes gradually evolved from typical dimple to quasi-cleavage and intergranular cracking. After aging at 480°C for 4 h and hydrogen charging for 12 h, the 40.9% HE susceptibility of ferrite-bearing samples was the lowest. In addition, the hydrogen permeation tests show that ferrite is a fast diffusion channel for hydrogen, and the ferrite-bearing samples have higher effective hydrogen diffusivity and lower hydrogen concentration.

There are a few studies of the ferrite effect on the HE properties of martensitic precipitation hardening stainless steel.

The purpose of this study is to develop the existence and mechanism of stress corrosion cracking (SCC) for A517 steel in marine environments.

Slow strain rate test (SSRT) and constant load tests were used to investigate the SCC susceptibility of A517 steel. In addition, the additive stresses caused by the corrosion film and hydrogen entering into steel were applied to reveal the fundamental mechanism of the SCC.

The SCC susceptibility increased due to anodic dissolution and additive stress caused by the corrosion-produced film under anode polarization. Furthermore, the SCC susceptibility increased with increasing cathodic polarization, which is due to the increased additional stress caused by hydrogen entering into the steel. However, when the cathode polarization further increased, the additional stress remained due to the constant hydrogen content, thus the SCC susceptibility did not vary. Moreover, the SCC susceptibility of A517 steel under an alternate immersion environment (AIE) was lower than that under a full immersion environment and the steel under the AIE with 0.5 W/D had the lowest SCC susceptibility.

The stress corrosion behaviors of A517 in marine environments under various conditions were systematically analyzed.

This study aims to report the CO₂ corrosion performance of 3Cr steel and 3Cr2Al steel and reveal the role of aluminum in mitigating corrosion of low-Cr steel.

Aluminum was added to 3Cr steel to prepare a new type of 3Cr2Al steel, and the effect of aluminum on the corrosion resistance of pipeline steel was studied using morphology observation and composition analysis, weight loss tests and electrochemical test.

In the CO₂/O₂ coexistence environment, the average corrosion rate of the 3Cr2Al steel was obviously lower than that of the 3Cr steel. The addition of aluminum expanded the range of prepassivation, and the dynamic potential polarization curve of 3Cr2Al steel showed duplex prepassivation phenomena. 3Cr steel underwent severe local corrosion, and 3Cr2Al steel underwent uniform corrosion. The addition of aluminum contributed to the formation of a dense corrosion product layer and greatly reduced the localized corrosion sensitivity.

The studies on CO₂ corrosion of aluminum containing low-Cr steel are quite rare. This study clarifies the role of aluminum by comparing the corrosion behavior of 3Cr2Al and 3Cr steel. The effect of aluminum on the growth of corrosion product film was discussed, and the duplex prepassivation phenomena of Cr and Al were revealed.

The purpose of this paper is to find out the anti‐smoking counselling frequency and its correlates in a sample of Chinese physicians.

In this paper, 268 physicians in Baoding, a city near Beijing, filled out a questionnaire asking about their own smoking status, their anti‐smoking behaviors as well as their opinions on how to reduce cigarette smoking in China.

The paper finds that 54 percent of the male and 8.4 percent of the female physicians were current cigarette smokers. When asked whether they had counselled their patients about cigarette smoking in the past year, 43.7 percent answered “always”; 38.1 percent “often”; 13.1 percent “sometimes”; 2.6 percent “occasionally”, and 2.6 percent said: “not much”. However, only 9.0 percent said that they were “very successful”. Physicians' anti‐smoking counselling practices were highly correlated with their own smoking status; whether they perceived their past anti‐smoking activities as successful; whether they thought that they should set examples by not smoking; whether they felt that they had the responsibility to help patients and whether they perceived themselves as influential in persuading patients to quit smoking.

The paper shows that messages aimed at increasing Chinese physicians' anti‐smoking counselling should appeal to their responsibility, exemplary role, and unique influence on patients' health‐related behaviors.

The paper adds to the few studies on Chinese physicians' cigarette smoking behavior and their anti‐smoking activities. In a country where cigarette smoking is a way of life among males, and few people are aware of the health consequences of cigarette smoking, physicians' efforts can be a spearhead to a cessation campaign.

Global economic growth provides new opportunities for the development of clothing enterprises, but at the same time, the rapid growth of clothing customization demand and the gradual increase of clothing costs also pose new challenges for the development of clothing enterprises. In this context, 3D printing technology is injecting new vitality and providing a new development direction for the vigorous development of clothing enterprises. However, with the application of 3D printing technology, more and more clothing enterprises are facing the problem of business model innovation. In view of the lack of relevant research, it is necessary to carry out exploratory research on this issue.

The business model canvas method was adopted to design business model for clothing enterprises using 3D printing. The simulation model of the designed business model was constructed by a system dynamics method, and the application of the designed business model was analysed by a scenario simulation.

Mass selective customization-centralized manufacturing (MSC-CM) business model was constructed for clothing enterprises using 3D printing, and a static display was carried out using the BMC method. A dynamic simulation model of the MSC-CM business model was constructed. The future scenario of clothing enterprises using 3D printing was developed, and a simulated enterprise was analysed. The results show that the MSC-CM business model has a good application value. The simulation model of the MSC-CM business model performs the function of a business strategy experiment platform and also has a good practical application value.

The MSC-CM business model is only a typical business model for clothing enterprises using 3D printing. It is necessary to further develop other business models, and some elements of the MSC-CM business model need to be further improved. In addition, the MSC-CM business model simulation uses a general model, which is not suitable for all clothing enterprises using 3D printing. When the model is applied, the relevant enterprises can further adjust and optimize it, thereby improving the validity of the simulation model.

To the best of the authors’ knowledge, this is the first paper on the MSC-CM business model for garment enterprises using 3D printing. Secondly, it is the first time that the business model of clothing enterprises using 3D printing has been simulated. In particular, the proposed business model simulation provides the possibility for testing the business strategy of clothing enterprises using 3D printing. In addition, a positive attempt has been made in the collaborative research of using both a static display business model and a dynamic simulation business model.

The purpose of this paper is to investigate the influence of embroidering technological parameters, of knitted material structure and of either using or not nonwoven material for backing on the quality of restangular embroidered element; based on the obtained results to select the optimal technological parameters for the embroidering of original clothing element avoiding the higher time expenses for the technical development process of new product.

The new methodology for the optimization of technology of original embroidered clothing element is based on the measurements of simple geometric element.

The methodology of technology optimisation based on the measurement of restangular element geometric parameters can also be applied for the optimization of the embroidering technology of advanced design elements.

The present study was carried out investigating knitted materials, but its methodology may be used for woven fabrics also, as their elongation rate is lower than one of knitted materials.

Development of the embroidering technology of original clothing element is based on the scientific approach and industrial experience.