Core Viewpoint - Fused quartz and quartz are both composed of silicon dioxide (SiO₂) but differ in manufacturing processes, purity levels, and specific characteristics, leading to unique applications and properties [1][4]. Group 1: Composition and Structure - Both fused quartz and quartz are primarily made of silicon dioxide (SiO₂) [3]. - Fused quartz is amorphous, lacking a crystal structure, while quartz has a crystalline structure [3]. Group 2: Manufacturing Process - Fused quartz is produced by melting high-purity silica sand at extremely high temperatures, resulting in a glass-like non-crystalline material [3]. - Quartz is a naturally occurring mineral that is processed after mining for various uses [3]. Group 3: Purity Levels - Fused quartz typically has a chemical purity exceeding 99.9%, making it suitable for applications requiring high optical clarity and chemical resistance [3]. - Natural quartz also has a high SiO₂ content but may contain trace impurities depending on its source [3]. Group 4: Thermal Properties - Fused quartz has a very low thermal expansion coefficient, providing strong thermal shock resistance, making it suitable for high-temperature applications [3]. - Quartz also has a low thermal expansion coefficient, but its crystalline structure can make it more susceptible to thermal stress under certain conditions [3]. Group 5: Optical Characteristics - Fused quartz offers excellent ultraviolet (UV) transmittance, making it ideal for lenses and other optical devices [3]. - While quartz also has good optical properties, fused quartz provides better transparency across a wider spectral range due to its amorphous structure [3]. Group 6: Electrical and Chemical Resistance - Fused quartz exhibits outstanding electrical insulation properties, making it suitable for electronic and semiconductor applications [3]. - Both materials have strong corrosion and chemical resistance, but fused quartz's higher purity often results in better performance in corrosive chemical environments [3]. Group 7: Applications - Fused quartz is commonly used in high-precision optical components, semiconductor manufacturing, and high-temperature lighting applications [3]. - Quartz is typically used in less demanding optical applications, as well as in the production of quartz glassware and industrial components [3]. Conclusion - Although fused quartz and quartz share the same chemical composition, they differ significantly in structure, performance, and applications, with fused quartz being particularly suited for demanding applications in optics, electronics, and high-temperature environments [4].

Core Viewpoint - Fused quartz and quartz are closely related but differ in manufacturing processes, purity levels, and specific characteristics, making them suitable for different applications [1][3]. Composition and Structure - Both fused quartz and quartz primarily consist of silicon dioxide (SiO₂), with fused quartz being amorphous and lacking a crystalline structure, while quartz has a crystalline structure [2]. - The amorphous structure of fused quartz is achieved through high-temperature melting, whereas quartz is naturally formed [2]. Manufacturing Process - Fused quartz is produced by melting high-purity silica sand at extremely high temperatures, resulting in a glass-like non-crystalline material, while quartz is a natural mineral that is mined and processed for various uses [2]. - The manufacturing process of fused quartz results in higher chemical purity compared to natural quartz [2]. Purity Levels - Fused quartz typically has a chemical purity exceeding 99.9%, while natural quartz also has a high SiO₂ content but may contain trace impurities depending on its source [2]. - The high purity of fused quartz makes it particularly suitable for applications requiring high optical clarity and chemical resistance [2]. Thermal Properties - Fused quartz has a very low thermal expansion coefficient, providing strong thermal shock resistance, making it suitable for high-temperature applications [2]. - Although quartz also has a low thermal expansion coefficient, its crystalline structure can make it more susceptible to thermal stress under certain conditions [2]. - Fused quartz has a high softening temperature of approximately 1670°C, allowing it to maintain structural integrity at elevated temperatures [2]. Optical Properties - Fused quartz exhibits excellent ultraviolet (UV) transmittance, making it an ideal material for lenses and other optical devices [2]. - While quartz also has good optical properties, the amorphous structure of fused quartz offers better transparency across a wider spectral range from UV to infrared [2]. - The high optical clarity and low scattering characteristics of fused quartz are particularly advantageous for precision optical applications [2]. Electrical and Chemical Resistance - Fused quartz provides outstanding electrical insulation properties, making it suitable for electronic and semiconductor applications [5]. - Both materials exhibit strong corrosion resistance and chemical inertness, but the higher purity of fused quartz typically results in better performance in corrosive chemical environments [5]. Applications - Fused quartz is commonly used in high-precision optical components, semiconductor manufacturing, and high-temperature lighting applications [5]. - Quartz is utilized in less demanding optical applications, as well as in the production of quartz glassware and industrial components [5]. - The superior performance of fused quartz makes it the preferred material for applications requiring extremely high purity, thermal stability, and optical clarity [5].

Core Viewpoint - The article discusses the development, production challenges, and applications of fused quartz, highlighting its growing importance in various high-tech industries and the need for improved production techniques to enhance quality and reduce costs [1][2][3]. Group 1: Classification of Fused Quartz - Fused quartz is classified into two main types: transparent quartz glass with SiO2 content greater than 99.95% and opaque quartz glass with SiO2 content greater than 99.80% [1]. - The industry has seen the development of new varieties, such as optical-grade fused quartz glass and high-purity fused quartz products, by companies like HERAEUS and GEQUARTZ [1]. Group 2: Production Status of Fused Quartz - Jiangsu Province's Donghai County is a key production base for high-purity quartz materials, with local companies using a production process that involves melting selected high-quality quartz raw materials [1]. - Major challenges in production include high melting temperatures, viscosity, and the need for high purity, with impurities needing to be less than 0.0001% [2]. - The current production methods often lead to high energy consumption, accounting for over 50% of production costs, which impacts profitability [2]. Group 3: Applications and Market Overview - Fused quartz is widely used in various fields, including electronics, military, aerospace, optical communications, and chemical engineering due to its excellent physical and chemical properties [3]. - In the electrical light source industry, fused quartz products are used in various lighting applications, including energy-saving lamps and sterilization lamps [4]. - The fiber optics industry relies heavily on high-purity fused quartz materials for the production of optical fibers, with strict requirements for size and purity [5]. - In aerospace, fused quartz is utilized for its low thermal expansion coefficient and excellent radiation resistance, making it suitable for applications in telescopes and spacecraft [5]. - The semiconductor industry has seen rapid growth in the use of fused quartz for various processes, including doping and diffusion of silicon wafers [5]. - Fused quartz is also essential in radar technology, chemical production, metallurgy, and precision instruments due to its stability and high-temperature resistance [5].