{"id":11463,"date":"2026-09-07T02:00:32","date_gmt":"2026-09-06T18:00:32","guid":{"rendered":"https:\/\/toquartz.com\/?p=11463"},"modified":"2026-03-03T14:46:29","modified_gmt":"2026-03-03T06:46:29","slug":"borosilicate-glass-vs-fused-quartz-tubes","status":"publish","type":"post","link":"https:\/\/toquartz.com\/ko\/borosilicate-glass-vs-fused-quartz-tubes\/","title":{"rendered":"Fused Quartz Tube or Borosilicate Glass Tube, Which One Suits for Your Application"},"content":{"rendered":"

Choosing the wrong tube material causes equipment failure, contaminated results, and costly downtime. Both materials look identical to the untrained eye, yet their performance boundaries diverge dramatically under real working conditions.<\/p>\n

This article delivers a complete, data-driven comparison of fused quartz tubes and borosilicate glass tubes across thermal, optical, chemical, and mechanical dimensions. Every major performance parameter is quantified, every application boundary is defined, and a structured selection framework is provided at the close.<\/p>\n

Material selection in high-stakes laboratory and industrial environments demands more than surface-level familiarity. Understanding the precise physical and chemical differences between these two tube materials is the foundational step toward making an informed, application-appropriate decision.<\/p>\n

\n

\"Transparent<\/p>\n

Two Distinct Materials with Fundamentally Different Compositions<\/h2>\n

Before any performance parameter can be meaningfully compared, the compositional identity of each material must be established with precision, because the atomic structure of a glass determines every downstream property it exhibits.<\/p>\n

Fused quartz is produced by melting naturally occurring high-purity quartz crystal or synthetic silicon tetrachloride at temperatures exceeding 1,700 \u00b0C, yielding a material composed of greater than 99.9% silicon dioxide (SiO\u2082) in an amorphous, non-crystalline state. The absence of network modifiers \u2014 elements such as boron, sodium, or aluminum \u2014 results in an exceptionally tight, homogeneous silica network. This structural purity is the origin of its extreme thermal stability, UV transparency, and chemical inertness. Depending on the raw material source and manufacturing method, fused quartz is further classified into four main types: Type I (electrically fused natural quartz), Type II (flame-fused natural quartz), Type III (synthetic silica from vapor-phase hydrolysis), and Type IV (synthetic silica from oxidation of SiCl\u2084). Each type carries slightly different hydroxyl (OH) content, which directly influences infrared absorption and UV performance.<\/p>\n

Borosilicate glass, by contrast, is a formulated multi-component glass. Its standard composition by weight percentage is approximately 70\u201380% SiO\u2082, 7\u201313% B\u2082O\u2083, 4\u20138% Na\u2082O or K\u2082O, and 2\u20137% Al\u2082O\u2083. The boron trioxide network former partially replaces silicon within the glass network, reducing the overall network rigidity compared to pure silica. Sodium and potassium oxides act as network modifiers, introducing ionic mobility into the structure. The most widely recognized borosilicate formulation is Corning's Borofloat 33 and the legacy Pyrex 7740, both sharing a thermal expansion coefficient near 3.3 \u00d7 10\u207b\u2076\/\u00b0C. The multi-component nature of borosilicate glass makes it significantly more economical to manufacture but simultaneously imposes fundamental performance ceilings that pure silica does not share.<\/p>\n

\n

\"High-Temperature<\/p>\n

Thermal Performance Boundaries of Fused Quartz Tubes and Borosilicate Glass Tubes<\/h2>\n

Among all differentiating properties, thermal behavior stands as the most operationally consequential, as the temperature envelope of a tube material directly dictates which processes it can serve without risk of structural failure.<\/p>\n

Thermal performance encompasses not only the maximum temperature ceiling but also the rate at which a material responds to temperature change, the point at which it begins to deform under its own weight, and the conditions under which permanent internal stress is introduced. Fused quartz tubes<\/a> and borosilicate glass tubes diverge sharply on every one of these sub-parameters, making a detailed thermal analysis indispensable for any serious material selection exercise.<\/p>\n

Maximum Operating Temperatures and Their Practical Implications<\/h3>\n

Fused quartz tubes carry a continuous service temperature of approximately 1,050\u20131,100 \u00b0C<\/strong>, with short-term exposure tolerance reaching up to 1,250 \u00b0C before viscous flow begins to compromise dimensional integrity. This ceiling is a direct consequence of the high softening point of pure SiO\u2082, which occurs at approximately 1,665 \u00b0C. In practice, semiconductor diffusion furnaces, high-temperature annealing systems, and crystal growth apparatus routinely operate fused quartz tubes at sustained temperatures between 900 \u00b0C and 1,100 \u00b0C without measurable deformation.<\/p>\n

Borosilicate glass tubes, by contrast, exhibit a practical continuous service limit of 450\u2013500 \u00b0C. The introduction of network-modifying oxides lowers the softening point to approximately 820 \u00b0C, and the annealing point \u2014 the temperature at which internal stress is relieved through atomic rearrangement \u2014 sits at roughly 560 \u00b0C. Operating borosilicate tubes above 500 \u00b0C in sustained applications produces slow viscous deformation, even if catastrophic failure does not occur immediately. Exceeding 550 \u00b0C in a loaded borosilicate tube configuration risks permanent sagging within hours of exposure.<\/strong><\/p>\n

The practical gap between 500 \u00b0C and 1,100 \u00b0C represents not merely a numerical difference but an entire category of industrial processes. Tube furnace CVD processes, thermal oxidation of silicon wafers, and high-temperature gas reaction studies all reside in this excluded zone for borosilicate, making fused quartz tubes the only viable candidate in these contexts.<\/p>\n

Thermal Shock Resistance as a Structural Differentiator<\/h3>\n

Thermal shock resistance is quantified through the coefficient of thermal expansion (CTE), which measures the fractional dimensional change per unit temperature increase. Fused quartz exhibits an exceptionally low CTE of approximately 0.55 \u00d7 10\u207b\u2076\/\u00b0C<\/strong>, one of the lowest values recorded for any inorganic glass or ceramic material. This near-zero expansion means that even when subjected to sudden temperature transitions \u2014 such as removing a tube from a 1,000 \u00b0C furnace and exposing it to ambient air \u2014 the differential thermal strain introduced across the tube wall remains far below the fracture threshold.<\/p>\n

Borosilicate glass, while significantly more thermal-shock resistant than soda-lime glass (CTE \u2248 9 \u00d7 10\u207b\u2076\/\u00b0C), carries a CTE of approximately 3.3 \u00d7 10\u207b\u2076\/\u00b0C \u2014 roughly six times higher than fused quartz. Laboratory protocols involving direct flame contact, rapid autoclave cycling, or sudden immersion in coolant fluids introduce thermal gradients that borosilicate can tolerate within modest limits. However, when temperature differentials across the tube wall exceed approximately 160 \u00b0C per centimeter of wall thickness, the tensile stress generated at the cooler surface approaches the material's modulus of rupture, creating fracture risk. Fused quartz, given its CTE, can withstand temperature differentials exceeding 1,000 \u00b0C without fracture<\/strong>, a performance envelope that borosilicate cannot approach.<\/p>\n

This structural difference manifests repeatedly in field conditions. Quartz tube replacement cycles in high-frequency thermal cycling furnaces are measured in years, whereas borosilicate equivalents in comparable \u2014 though lower temperature \u2014 cycling environments require replacement on a monthly or quarterly basis.<\/p>\n

Softening Point, Annealing Point and Strain Point Data<\/h3>\n

Three critical thermal landmarks define the safe operational envelope of any glass material: the strain point, the annealing point, and the softening point. Below the strain point, a glass can be cooled at any rate without introducing permanent stress.<\/strong> Between the strain point and the annealing point, stress relief occurs over time. Above the softening point, the material flows under its own weight.<\/p>\n

For fused quartz, the strain point is approximately 1,070 \u00b0C, the annealing point approximately 1,140 \u00b0C, and the softening point approximately 1,665 \u00b0C. These values confirm that fused quartz retains full dimensional rigidity well above the operating temperature of most industrial high-temperature processes. For borosilicate glass (Type Borofloat 33 \/ Pyrex 7740), the strain point is approximately 515 \u00b0C, the annealing point approximately 565 \u00b0C, and the softening point approximately 820 \u00b0C.<\/p>\n

The 555 \u00b0C gap between the softening points of these two materials is not a marginal engineering tolerance \u2014 it is a categorical boundary<\/strong> that separates low-to-medium temperature applications from high-temperature industrial processes.<\/p>\n

Key Thermal Property Data<\/h4>\n\n\n\n\n\n\n\n\n\n\n\n
\uc5f4 \uc18d\uc131<\/th>\n\ud4e8\uc988\ub4dc \ucffc\uce20<\/th>\n\ubd95\uaddc\uc0b0 \uc720\ub9ac<\/th>\n<\/tr>\n<\/thead>\n
Max Continuous Service Temp (\u00b0C)<\/td>\n1,050-1,100<\/td>\n450-500<\/td>\n<\/tr>\n
Short-Term Peak Tolerance (\u00b0C)<\/td>\n~1,250<\/td>\n~550<\/td>\n<\/tr>\n
\uc5f0\ud654\uc810(\u00b0C)<\/td>\n~1,665<\/td>\n~820<\/td>\n<\/tr>\n
\uc5b4\ub2d0\ub9c1 \ud3ec\uc778\ud2b8(\u00b0C)<\/td>\n~1,140<\/td>\n~565<\/td>\n<\/tr>\n
\uc2a4\ud2b8\ub808\uc778 \ud3ec\uc778\ud2b8(\u00b0C)<\/td>\n~1,070<\/td>\n~515<\/td>\n<\/tr>\n
CTE(\u00d710-\u2076\/\u00b0C)<\/td>\n~0.55<\/td>\n~3.3<\/td>\n<\/tr>\n
Max Thermal Shock \u0394T (\u00b0C)<\/td>\n>1,000<\/td>\n~160<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n
\n

\"UV-Transmissive<\/p>\n

Optical Transmission Profiles Across Fused Quartz Tubes and Borosilicate Variants<\/h2>\n

Optical performance is rarely the first property mentioned in general materials specifications, yet for photochemical, spectroscopic, and UV-processing applications, it frequently becomes the sole decisive criterion.<\/p>\n

The transmission spectrum of a tube material determines whether ultraviolet radiation, visible light, or near-infrared energy can pass through the tube wall with sufficient intensity to serve the intended function. Fused quartz tubes and borosilicate variants occupy fundamentally different portions of the electromagnetic spectrum in terms of practical transmission, and understanding this distinction at the quantitative level is essential for any application involving light-matter interaction.<\/p>\n

UV Transmission Windows and Wavelength Cutoff Values<\/h3>\n

Fused quartz tubes transmit ultraviolet radiation from approximately 150 nm (vacuum UV) to well beyond 4,000 nm in the infrared<\/strong>, with transmission values exceeding 90% across much of this range in standard wall thicknesses. Synthetic fused silica (Type III and IV) achieves even deeper UV penetration, with practical transmission down to approximately 160\u2013170 nm. At 200 nm \u2014 a wavelength critical for deep UV sterilization, photolithography alignment systems, and ozone generation lamps \u2014 fused quartz transmits approximately 85\u201390% of incident radiation through a 1 mm wall.<\/p>\n

Borosilicate glass presents a fundamentally different spectral profile. The UV cutoff wavelength for standard borosilicate glass occurs at approximately 300\u2013320 nm<\/strong>, meaning that radiation below this threshold is almost entirely absorbed by the glass matrix rather than transmitted. This absorption is caused by the iron oxide impurities inherent in natural raw materials and by the fundamental electronic absorption edge of the borosilicate network itself. At 254 nm \u2014 the germicidal UV wavelength used in sterilization and photocatalysis \u2014 borosilicate glass transmits less than 1% of incident UV energy through a 1 mm wall, rendering it functionally opaque at this wavelength.<\/p>\n

This 150 nm cutoff gap between the two materials defines an unbridgeable performance divide for UV-dependent applications. No surface treatment or wall thickness reduction can extend borosilicate's UV transmission below its fundamental absorption edge.<\/p>\n

Infrared and Visible Range Transmission Comparison<\/h3>\n

In the visible spectrum (400\u2013700 nm), both materials perform comparably, with transmission values in the 90\u201392% range for typical wall thicknesses of 1\u20132 mm, excluding surface reflection losses. The slight greenish tint visually observable at the cut ends of borosilicate tubes corresponds to minor absorption bands introduced by iron and other trace oxides, but this has negligible practical impact on most visible-light applications.<\/p>\n

In the near-infrared (NIR) range from 700 nm to approximately 2,500 nm, both materials again transmit comparably<\/strong>, with fused quartz maintaining high transmission up to approximately 3,500\u20134,000 nm before the strong Si\u2013O stretching absorption bands cause significant attenuation. Borosilicate glass exhibits similar NIR transmission up to approximately 2,500 nm, beyond which B\u2013O absorption bands introduce additional losses not present in pure fused silica.<\/p>\n

The mid-infrared range (2,500\u20135,000 nm) marks a significant divergence. Fused quartz, particularly low-OH synthetic variants (Type IV), maintains measurable transmission between 2,700 nm and 3,500 nm with OH absorption bands suppressed, whereas borosilicate glass becomes effectively opaque above 2,500 nm. For thermophotovoltaic systems, infrared gas sensing, or mid-IR spectroscopy, fused quartz is the only viable tube material of the two.<\/strong><\/p>\n

Fluorescence and Autofluorescence Behavior Under Illumination<\/h3>\n

Autofluorescence<\/a>1<\/a><\/sup> \u2014 the emission of light by a material when excited by radiation \u2014 is a critical consideration in fluorescence microscopy, Raman spectroscopy, and any application in which background signal interference must be minimized. Fused quartz exhibits extremely low intrinsic fluorescence<\/strong>, particularly when manufactured from high-purity synthetic silica feedstock. Type III and Type IV fused silica tubes show autofluorescence levels orders of magnitude lower than silicate-based glass compositions when excited at wavelengths between 250 nm and 500 nm.<\/p>\n

Borosilicate glass, owing to its multi-component formulation, contains trace quantities of rare earth elements, transition metals, and organic contaminants introduced during raw material processing. These impurities generate measurable background fluorescence when excited by UV or near-UV radiation. At excitation wavelengths of 365 nm, standard borosilicate glass emits fluorescence in the blue-green range with intensities that can mask weak sample signals by factors of 10\u2013100\u00d7 in sensitive spectroscopic applications.<\/p>\n

For Raman spectroscopy flow cells, single-molecule fluorescence assays, and laser-coupled fiber optic systems, this autofluorescence difference alone makes fused quartz the technically mandated choice<\/strong>, regardless of any other parameter comparison.<\/p>\n

Optical Transmission Comparison<\/h4>\n\n\n\n\n\n\n\n\n\n\n
\uad11\ud559 \uc18d\uc131<\/th>\n\ud4e8\uc988\ub4dc \ucffc\uce20<\/th>\n\ubd95\uaddc\uc0b0 \uc720\ub9ac<\/th>\n<\/tr>\n<\/thead>\n
UV \ucc28\ub2e8 \ud30c\uc7a5(nm)<\/td>\n~150 (synthetic)<\/td>\n~300\u2013320<\/td>\n<\/tr>\n
200 nm\uc5d0\uc11c\uc758 \ud22c\uacfc\uc728 (%)<\/td>\n~85\u201390<\/td>\n<5<\/td>\n<\/tr>\n
254nm(%)\uc5d0\uc11c \uc804\uc1a1<\/td>\n~90<\/td>\n<1<\/td>\n<\/tr>\n
\uac00\uc2dc \ubc94\uc704 \uc804\uc1a1(%)<\/td>\n~90\u201392<\/td>\n~90\u201392<\/td>\n<\/tr>\n
NIR Transmission Upper Limit (nm)<\/td>\n~3,500\u20134,000<\/td>\n~2,500<\/td>\n<\/tr>\n
Autofluorescence (365 nm excitation)<\/td>\n\ub9e4\uc6b0 \ub0ae\uc74c<\/td>\n\ubcf4\ud1b5-\ub192\uc74c<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n
\n

\"Chemically<\/p>\n

Chemical Durability and Resistance Profiles<\/h2>\n

Chemical compatibility determines whether a tube material will maintain its structural and surface integrity over time when exposed to the reactive environments present in laboratory reactors, industrial process lines, and high-purity fluid handling systems.<\/p>\n

The long-term chemical durability of a tube material is as important as its short-term corrosion resistance. Surface leaching, ion migration, and progressive network dissolution can compromise both the tube itself and the purity of the media it contacts. Fused quartz and borosilicate glass respond to chemical environments through fundamentally different mechanisms, and understanding both the immediate and cumulative effects of chemical exposure is essential for accurate service life prediction.<\/p>\n

Resistance to Acids, Bases and Organic Solvents<\/h3>\n

Fused quartz demonstrates outstanding resistance to virtually all mineral acids, including hydrochloric acid (HCl), sulfuric acid (H\u2082SO\u2084), nitric acid (HNO\u2083), and phosphoric acid (H\u2083PO\u2084) across the full concentration range and at elevated temperatures. The single critical exception is hydrofluoric acid (HF) and fluorine-containing compounds<\/strong>, which react directly with the Si\u2013O\u2013Si network, progressively etching the surface at rates that vary with HF concentration and temperature. At 5% HF concentration and 25 \u00b0C, fused quartz dissolves at approximately 0.04 \u00b5m\/min, a rate that accelerates significantly above 50 \u00b0C.<\/p>\n

Borosilicate glass is similarly resistant to most mineral acids under moderate conditions, but its multi-component composition introduces additional chemical attack pathways. Hydrofluoric acid attacks borosilicate at rates comparable to or faster than those observed for fused quartz<\/strong>, and hot concentrated alkali solutions \u2014 particularly NaOH and KOH above 70 \u00b0C \u2014 leach boron and alkali ions from the glass network at substantially higher rates than observed with fused quartz. Dissolution rates of borosilicate in 10% NaOH at 95 \u00b0C can reach 0.5\u20132 \u00b5m\/min, approximately 10\u201350\u00d7 faster than equivalent attack on fused quartz under the same conditions.<\/p>\n

Both materials show broad resistance to organic solvents including acetone, ethanol, toluene, and chlorinated solvents. No significant chemical attack is observed for either material in contact with common organic media<\/strong> at temperatures below their respective service ceilings, making this parameter non-discriminating for most solvent-phase applications.<\/p>\n

Behavior Under High-Purity Process Conditions<\/h3>\n

In semiconductor wafer processing, pharmaceutical manufacturing, and high-purity analytical chemistry, the chemical concern shifts from gross corrosion resistance to trace contamination \u2014 specifically, the leaching of metallic ions from the tube wall into the process stream. Fused quartz manufactured to semiconductor-grade specifications contains total metallic impurity levels below 1 ppm by weight<\/strong>, with individual elements such as Al, Fe, Ca, and Na present at concentrations in the range of 1\u2013100 ppb. Under typical process conditions, ion leaching from semiconductor-grade fused quartz into ultrapure water at 80 \u00b0C is measured at sub-ppb levels per cm\u00b2 of tube surface area.<\/p>\n

Borosilicate glass, by contrast, leaches measurable quantities of boron, sodium, and potassium ions even under mild aqueous conditions. The rate of boron leaching from standard borosilicate glass into water at 25 \u00b0C is approximately 0.02\u20130.1 \u00b5g\/cm\u00b2\u00b7h, a level that is acceptable for general laboratory glassware but entirely unacceptable for semiconductor process tubes, high-performance liquid chromatography (HPLC) systems, or cell culture bioreactor tubes where ion contamination can affect yield or biological response. The sodium content of standard borosilicate glass \u2014 typically 4\u20138 wt% as Na\u2082O \u2014 is a persistent contamination source<\/strong> that cannot be eliminated through cleaning protocols alone.<\/p>\n

Pharmaceutical-grade borosilicate glass (Type I, complying with USP, EP, and ISO 4802 standards) is manufactured with tighter compositional control to minimize leaching, and is widely used in parenteral drug packaging. However, even Type I borosilicate glass does not achieve the metallic purity levels of semiconductor-grade fused quartz, and cannot be substituted in process applications where parts-per-trillion contamination limits are enforced.<\/p>\n

Long-Term Stability Under Repeated Chemical Exposure<\/h3>\n

Repeated chemical cleaning cycles \u2014 a standard maintenance practice in laboratory and process environments \u2014 introduce cumulative surface degradation that differs substantially between the two materials. Fused quartz subjected to repeated piranha solution cleaning (H\u2082SO\u2084:H\u2082O\u2082, 3:1) cycles shows a surface roughness increase of less than 0.5 nm RMS after 50 cycles<\/strong>, as measured by atomic force microscopy, confirming exceptional surface stability under aggressive oxidative cleaning conditions.<\/p>\n

Borosilicate glass under the same cleaning protocol exhibits progressive leaching of boron and alkali modifiers from the outermost surface layer, creating a silica-rich depleted zone. While this depletion layer offers some temporary increase in chemical resistance, it is mechanically fragile and susceptible to spallation under thermal cycling. After 20\u201330 aggressive cleaning cycles, the interior surface of borosilicate tubes can show measurable increases in ion leaching rates as the depleted layer is physically disrupted. Surface pitting and microcrack initiation at surface defect sites have been reported after 30+ aggressive acid-base alternating cleaning cycles<\/strong> in borosilicate laboratory tubing used in analytical chemistry workflows.<\/p>\n

The long-term consequence of this difference is a significantly shorter functional service life for borosilicate tubes in chemically intensive applications, not because of catastrophic failure but because of the gradual accumulation of surface degradation that compromises both tube integrity and process purity over time.<\/p>\n

\ub0b4\ud654\ud559\uc131 \uc694\uc57d<\/h4>\n\n\n\n\n\n\n\n\n\n\n\n\n
\ud654\ud559 \ubb3c\uc9c8<\/th>\n\uc6a9\uc735 \uc11d\uc601 \uc800\ud56d\uccb4<\/th>\n\ubd95\uaddc\uc0b0 \uc720\ub9ac \uc800\ud56d<\/th>\n<\/tr>\n<\/thead>\n
Hydrochloric Acid (all conc.)<\/td>\n\uc6b0\uc218<\/td>\n\uc6b0\uc218<\/td>\n<\/tr>\n
Sulfuric Acid (all conc.)<\/td>\n\uc6b0\uc218<\/td>\n\uc6b0\uc218<\/td>\n<\/tr>\n
\ubd88\ud654\uc218\uc18c\uc0b0<\/td>\nPoor (attacked)<\/td>\nPoor (attacked)<\/td>\n<\/tr>\n
NaOH 10% at 95\u00b0C (\u00b5m\/min)<\/td>\n~0.01\u20130.05<\/td>\n~0.5\u20132.0<\/td>\n<\/tr>\n
\uc720\uae30 \uc6a9\uc81c<\/td>\n\uc6b0\uc218<\/td>\n\uc6b0\uc218<\/td>\n<\/tr>\n
Boron Ion Leaching<\/td>\n\uc5c6\uc74c<\/td>\nModerate (0.02\u20130.1 \u00b5g\/cm\u00b2\u00b7h)<\/td>\n<\/tr>\n
Na\/K Ion Leaching<\/td>\nNegligible (<ppb)<\/td>\n\uce21\uc815 \uac00\ub2a5<\/td>\n<\/tr>\n
Resistance After 50 Cleaning Cycles<\/td>\nSurface RMS <0.5 nm<\/td>\nProgressive degradation<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n
\n

\"Dimensionally<\/p>\n

Mechanical Strength and Dimensional Stability<\/h2>\n

Mechanical performance, while rarely the primary selection criterion for tube materials in thermochemical applications, constitutes a necessary secondary parameter in any system where the tube must bear mechanical load, withstand internal pressure, or maintain precise dimensional tolerances across a service lifetime.<\/p>\n