Stainless Steel Casting for Surface
Introduction
In the highly competitive field of stainless steel casting, EATHU has emerged as a leading force, dedicated to continuous innovation and improvement. Surface roughness of stainless steel castings is a crucial factor that significantly affects the quality and performance of the final products. EATHU has been committed to exploring and implementing advanced practices and innovative measures to address this issue and meet the diverse and stringent requirements of various industries.
EATHU's Outstanding Practices and Innovative Measures in the Field of Stainless Steel Casting
(1) Advanced Material Research and Optimization
EATHU has always placed material innovation at the core of its corporate development strategy. In response to the problem of surface roughness of stainless steel castings, it has invested a large amount of manpower, material resources, and financial resources in material research and optimization. The company has assembled an interdisciplinary research and development team consisting of materials scientists, metallurgical engineers, and casting process experts, dedicated to in-depth research on the relationship between the microstructure and properties of stainless steel materials.
By employing advanced material analysis techniques such as scanning electron microscopy (SEM), X-ray diffraction (XRD), and energy-dispersive spectroscopy (EDS), the crystal structure, pore distribution, and elemental composition of stainless steel materials are precisely characterized and analyzed. Based on these in-depth research results, EATHU has developed a series of new stainless steel material formulations with independent intellectual property rights. These formulations effectively regulate the crystallization process of stainless steel by optimizing the types and proportions of alloying elements, significantly reducing the number and size of pores in the columnar crystal structure network, and thus reducing the possibility of molten metal infiltrating into the pores from the source, laying a solid material foundation for obtaining stainless steel castings with a smooth surface.
For example, when developing a stainless steel material for casting the shell of high-end medical devices, EATHU's research and development team successfully changed the crystal growth direction and rate of stainless steel by adding specific trace elements, making the crystal structure more compact and uniform, and reducing the porosity by more than 30%. After actual casting tests, the surface roughness of the medical device shell cast with this new material was significantly reduced, reaching the industry-leading level, while also improving the biocompatibility and corrosion resistance of the material.
(2) Precision Manufacturing Process Control
EATHU has a strict and precise process control system in the manufacturing process of stainless steel casting. Like a highly skilled craftsman, it meticulously polishes every process detail, striving to minimize the surface roughness of stainless steel castings.
In the casting process, EATHU has independently developed and applied an advanced temperature control system that can monitor and regulate the preheating temperature of stainless steel, the pouring temperature of molten metal, the mold temperature, and the cooling temperature in real-time and precisely. Through a large number of experimental studies and data analysis, a comprehensive temperature-roughness mathematical model has been established. According to the different stainless steel materials and casting structure characteristics, the optimal combination of temperature parameters is accurately set. For example, when casting a complex-structured stainless steel automotive part, the optimal pouring temperature and mold temperature calculated by this model enable the molten metal to maintain good fluidity during the filling process and effectively control the depth of its infiltration into the pores, ultimately reducing the surface roughness of the casting by 25%.
At the same time, EATHU also conducts refined management of the pouring head and vacuum degree. The company has introduced high-precision pressure sensors and vacuum degree measuring instruments to monitor the pressure changes during the pouring process in real-time and precisely adjust the pouring head size and vacuum degree through an automated control system. When pouring a large stainless steel pump body casting, by precisely controlling the pouring head and vacuum degree, the splashing and turbulence of the molten metal are effectively avoided, the gas entrainment and pore formation are reduced, and the surface quality of the casting is significantly improved.
In the investment mold and die manufacturing process, EATHU adopts internationally leading high-speed machining centers and precision mold manufacturing technologies to ensure that the flatness and smoothness of the die surface reach micron-level precision. For example, when manufacturing the die for stainless steel precision castings used in aerospace, the five-axis simultaneous machining technology is used to machine extremely complex and highly precise mold cavities, and the surface roughness Ra value can be controlled below 0.2μm. At the same time, EATHU has also developed specialized process parameter optimization software for different investment mold methods. Through a combination of simulation analysis and practical verification, the optimal investment mold manufacturing process parameters are determined. When using the lost wax method to make investment molds, this software can accurately calculate the optimal wax liquid temperature, injection pressure, and holding time according to the characteristics of the wax material, the shape and size of the casting, significantly improving the surface quality of the investment mold and providing a high-quality investment mold basis for the subsequent pouring process.
(3) Customized Solution
EATHU is well aware that different industries and customers have significant differences in the surface quality requirements of stainless steel castings. Therefore, relying on its strong technological research and development strength and rich production experience, the company provides customized stainless steel casting solutions for customers.
In the initial stage of communication and cooperation with customers, EATHU's professional technical team will deeply understand the customer's product application scenarios, performance requirements, and surface quality expectations. For example, for customers in the food processing industry, in addition to requiring stainless steel castings to have good corrosion resistance and mechanical properties, they also have extremely high hygiene standard requirements for surface roughness. The surface must be smooth and flat, without any gaps or depressions that may breed bacteria; while for customers in the building decoration industry, they pay more attention to the aesthetic appearance and decorative effect of stainless steel castings and may require specific surface textures or gloss levels.
Based on the personalized needs of customers, EATHU will conduct customized planning from material selection, manufacturing process design to post-treatment process. In material selection, according to the different requirements of customers for corrosion resistance, strength, and surface quality, the most suitable stainless steel material or custom alloy material is recommended for them. In manufacturing process design, according to the shape, size, and complexity of the customer's product, the casting process parameters, investment mold method, and die design are optimized to ensure that the best surface quality is achieved while meeting the product performance requirements. For example, when producing stainless steel watch case castings for a high-end watch manufacturer, EATHU adopted micro-casting technology, combined with special polishing and passivation post-treatment processes, making the watch case surface present a mirror-like luster and extremely low surface roughness, meeting the customer's strict requirements for the refined appearance of the product.
In the post-treatment process, EATHU provides a variety of surface treatment processes for customers to choose from, such as mechanical polishing, electrochemical polishing, sandblasting, passivation, etc., and combines them according to customer needs. For example, for some stainless steel castings that need to improve surface hardness and wear resistance, EATHU will first perform mechanical polishing to remove surface defects, and then conduct nitriding treatment or electroplating hard chrome treatment, improving surface performance while further improving surface roughness and appearance.
(4) Strict Quality Inspection and Continuous Improvement
EATHU has established a comprehensive, multi-level strict quality inspection system, like a tight quality monitoring network, to conduct comprehensive and accurate inspection and control of the surface quality of stainless steel castings.
In the raw material inspection process, in addition to the routine inspection of the chemical composition and mechanical properties of stainless steel raw materials, the microstructure and surface state of the materials are also analyzed. Advanced equipment such as atomic force microscopy (AFM) and laser confocal microscopy is used to detect indicators such as the porosity, roughness, and crystal defects of the raw material surface, ensuring that the quality of the raw materials meets high-standard requirements. Only raw materials that pass strict inspection can enter the production process, ensuring the quality of stainless steel castings from the source.
During the production process, EATHU has set strict quality inspection points for each process, using a combination of online inspection and offline sampling inspection to monitor the surface quality of the castings in real-time. For example, after the investment mold is completed, the surface roughness of the investment mold is immediately detected using a profilometer. If the surface roughness exceeds the set standard, the cause is immediately traced and adjusted or scrapped; after pouring is completed, X-ray flaw detection and ultrasonic flaw detection technologies are used to detect the internal quality of the casting, and at the same time, a three-dimensional optical measuring instrument is used to comprehensively detect the surface contour and roughness of the casting, ensuring that the casting surface has no pores, shrinkage cavities, slag inclusions, and other defects, and the surface roughness meets customer requirements.
In the finished product inspection process, EATHU not only conducts routine appearance inspection, dimensional measurement, and performance testing but also specifically conducts high-precision inspection and evaluation of surface roughness. The company is equipped with several internationally advanced surface roughness measuring instruments, such as Taylor Hobson roughness meters, which can accurately measure various roughness parameters such as Ra, Rz, and Ry of the casting surface and compare and analyze them with the customer's required standards. Products with surface roughness that does not meet the standard are not allowed to enter the market and are all reworked or scrapped.
In addition, EATHU has also established a complete quality feedback and continuous improvement mechanism. Regularly collect customer feedback on the surface quality of stainless steel castings, conduct in-depth analysis and summary of the quality problems that occur during the production process, and identify the root causes of the problems. Through the implementation of quality improvement projects, organize technical personnel and production workers to conduct technical research and process optimization, continuously improve and enhance the surface quality of stainless steel castings. For example, after a batch of stainless steel castings had a relatively large fluctuation in surface roughness, EATHU quickly established a quality improvement team. Through the investigation and analysis of various factors such as raw materials, manufacturing process, and equipment status, it was found that the temperature control system of a certain pouring device had a malfunction, resulting in unstable pouring temperature. In response to this problem, EATHU carried out a comprehensive repair and upgrade of the equipment, optimized the temperature control algorithm, and trained and assessed the relevant operators. After a series of improvement measures, the problem of surface roughness fluctuation was successfully solved, and the stability of product quality was improved.