The “degree” of a diamond drill bit is a critical technical parameter that primarily refers to two core characteristics: matrix hardness (measured by hardness scales like HRC, HRB, or Rockwell) and cutting edge angle (the angle formed by the drill bit’s tip and its cutting surface). These two factors directly determine the drill bit’s performance, compatibility with different materials, durability, and drilling efficiency. Unlike the “degree” of tools like saw blades (which may refer to tooth count or bevel angle), diamond drill bits rely on their diamond grit (embedded in a metal matrix) to cut through hard materials—so their “degree” is not a single value but a combination of matrix hardness and edge geometry, each tailored to specific drilling tasks. To fully understand what this degree represents, we must break down its components, explore how they interact, and connect them to real-world applications, alongside detailed analyses of leading brands and their representative models, which illustrate how degree specifications translate to practical use.

First, matrix hardness is the most common reference when discussing a diamond drill bit’s “degree.” The matrix is the metal alloy (typically cobalt-based, copper-based, iron-based, or a composite) that holds the diamond grit in place. Its hardness directly impacts how well the matrix retains the diamond particles during drilling and how quickly it wears down to expose new, sharp diamonds (a process called “self-sharpening”). Harder matrices (higher HRC degrees) retain diamonds longer but wear more slowly, making them ideal for extremely hard materials (e.g., reinforced concrete, granite). Softer matrices (lower HRC degrees) wear faster, exposing new diamonds more quickly, which is better for softer, abrasive materials (e.g., tile, marble) that would otherwise dull diamond grit prematurely. For example, a drill bit with a matrix hardness of HRC 30–35 (low degree) is designed for glass or ceramic tile—materials that are hard but brittle; a softer matrix prevents excessive pressure on the material (avoiding cracks) while ensuring frequent diamond renewal. In contrast, a drill bit with HRC 45–55 (high degree) is used for reinforced concrete or basalt, where the hard matrix resists wear from the material’s aggregate and steel rebar, maintaining cutting efficiency over dozens of holes.

Matrix hardness is measured using the Rockwell Hardness Scale, with “HRC” (Rockwell C Scale) being the standard for hard metals (like cobalt-based matrices) and “HRB” (Rockwell B Scale) for softer alloys (like copper-based matrices). A key point is that matrix hardness is not arbitrary: manufacturers calibrate it based on the diamond grit’s quality (size, purity, and concentration). For instance, a drill bit with high-purity diamond grit (99.9% carbon) may use a harder matrix (HRC 50) to maximize grit retention, while a budget-friendly bit with lower-purity grit (mixed with graphite) may use a softer matrix (HRC 32) to compensate for faster grit dulling. This balance ensures that the drill bit neither loses diamonds too quickly (leading to premature failure) nor retains dull grit (reducing drilling speed).

Second, cutting edge angle is the second component of a diamond drill bit’s “degree,” referring to the angle between the two cutting surfaces at the bit’s tip. Common angles range from 118° to 135°, with each angle optimized for specific materials. A narrower angle (118°) creates a sharper tip, which is ideal for brittle materials like glass, ceramic, or porcelain. The sharp tip reduces contact area with the material, minimizing pressure and preventing cracks—critical for materials that break easily under force. For example, when drilling a hole in a glass shower door, a 118° edge angle allows the diamond grit to score the glass smoothly without chipping the edges. In contrast, a wider angle (135°) creates a more robust tip, which distributes pressure evenly and resists damage when drilling hard, abrasive materials like concrete or granite. The wider angle also helps dissipate heat (a byproduct of drilling hard materials) and prevents the tip from “walking” (slipping off the drilling mark) during use. For instance, a 135° edge angle is standard for concrete drill bits used in construction, as it can withstand the impact of hitting steel rebar without bending or dulling.

Some specialized diamond drill bits have non-standard edge angles (e.g., 90° for flat-bottomed holes in stone countertops or 150° for deep-hole drilling in masonry). These angles are not random—they are engineered to solve specific problems: a 90° angle ensures the hole’s bottom is flat (essential for installing sink drains), while a 150° angle reduces friction in deep holes by allowing debris to escape more easily. Thus, the cutting edge angle is a “degree” parameter that directly influences the drill bit’s ability to handle material properties (brittleness, hardness, abrasiveness) and the desired hole quality (smoothness, depth, shape).

To fully grasp how these “degree” parameters work in practice, it is essential to examine leading diamond drill bit brands and their representative models, as each brand tailors matrix hardness and edge angles to target markets (home use, professional construction, industrial manufacturing). Below is a detailed breakdown of top brands, their key models, and how their degree specifications align with use cases.

Bosch is a global leader in power tools and accessories, known for balancing performance and affordability. Its diamond drill bits cover a range of degrees, from low-HRC models for home tile drilling to high-HRC options for professional concrete work.

This model is designed for home and DIY use, targeting materials like ceramic tile, glass, and marble. Its matrix hardness is rated at HRC 35 (soft to medium), which is ideal for these brittle, low-abrasion materials. The softer matrix wears down gradually, exposing new diamond grit to maintain cutting sharpness—critical for avoiding tile chipping, a common issue with harder matrices that apply too much pressure. The cutting edge angle is 118°, a narrow angle that creates a sharp tip to score tile and glass without cracking. In terms of specifications, the HC850 has an overall length of 100mm (working length: 50mm) and a 3mm shank that fits most standard 手电钻 (corded or cordless). It uses 40/50 mesh diamond grit (medium-fine), which provides a smooth hole finish—essential for installing bathroom fixtures (e.g., towel bars, toilet paper holders) where rough edges would be visible. The bit also features a spiral flute design that channels water (used for cooling) and debris away from the tip, reducing heat buildup. In real-world use, the HC850 can drill 50–80 holes in standard ceramic tile (10mm thick) before needing replacement, making it a cost-effective choice for DIYers. It is priced at approximately $8–$12 per unit, available in packs of 1 or 3.

A step up for light professional use, this model is optimized for drilling in soft concrete (C20–C25 grade) and natural marble. Its matrix hardness is HRC 42 (medium), a balance between wear resistance and self-sharpening—sufficient to handle concrete’s aggregate (sand, gravel) without wearing out too quickly. The cutting edge angle is 125°, a middle ground that combines the sharpness of 118° (for marble) and the durability of 135° (for concrete). The HC5060 has an overall length of 150mm (working length: 80mm) and a 1/4-inch hex shank, compatible with impact drills (common on job sites). It uses 30/40 mesh diamond grit (coarser than the HC850), which increases drilling speed in concrete—important for professionals who need to complete tasks efficiently. A key feature is its cobalt-infused matrix, which enhances corrosion resistance (useful for outdoor projects where the bit may be exposed to rain). In testing, the HC5060 can drill 30–50 holes in C25 concrete (150mm thick) or 100–120 holes in marble before grit dulling. It is priced at $15–$20 per unit, popular among small construction companies and handymen.

Bosch’s industrial-grade model, the HC900 is built for heavy-duty drilling in reinforced concrete (C30–C40 grade) and granite. Its matrix hardness is HRC 52 (high), one of the hardest in Bosch’s lineup—designed to resist wear from steel rebar and granite’s high abrasiveness (莫氏硬度 6–7). The cutting edge angle is 135°, a wide angle that distributes pressure evenly when hitting rebar, preventing tip damage. The HC900 has an overall length of 200mm (working length: 120mm) and a 5/8-inch shank, compatible with large hammer drills and 台钻 (table drills) used in commercial construction. It uses 20/30 mesh diamond grit (extra-coarse) for maximum cutting power, and its matrix is made of a tungsten-cobalt alloy (instead of standard cobalt) for superior durability. A unique feature is its double-layer diamond coating—a top layer for initial cutting and a bottom layer for extended use—extending the bit’s lifespan by 50% compared to the HC5060. In industrial settings, the HC900 can drill 80–100 holes in C35 reinforced concrete (200mm thick) before needing replacement. It is priced at $35–$45 per unit, used by commercial contractors for projects like installing electrical conduit or plumbing pipes.

DeWalt is synonymous with rugged, job site-ready tools, and its diamond drill bits focus on high-HRC matrices and durable edge angles for heavy use. The brand targets professional contractors, so its models prioritize longevity and consistent performance over low cost.

A mid-range professional model, the DW5470 is designed for drilling in medium-hard materials: limestone, travertine, and light reinforced concrete (C25 grade). Its matrix hardness is HRC 48 (medium-high), which balances wear resistance (for concrete) and self-sharpening (for limestone, a soft but abrasive stone). The cutting edge angle is 130°, a slightly narrower wide angle that improves drilling speed in limestone while still withstanding concrete’s aggregate. The DW5470 has an overall length of 160mm (working length: 90mm) and a 1/4-inch hex shank with DeWalt’s Secure-Grip design—a textured surface that prevents slippage in impact drills, even when wet. It uses 35/45 mesh diamond grit (medium-coarse) and a heat-treated matrix, which reduces warping during high-speed drilling (common in professional use, where drills operate at 1,500–2,000 RPM). In field tests, the DW5470 can drill 40–60 holes in C25 concrete or 150–180 holes in travertine before grit wear. It is priced at $18–$25 per unit, a favorite among residential contractors for kitchen and bathroom renovations (e.g., drilling holes for backsplash tiles or vanity plumbing).

Built for heavy reinforced concrete (C35–C40 grade) and granite, the DW5490 is a workhorse for commercial construction. Its matrix hardness is HRC 55 (very high), the hardest in DeWalt’s consumer lineup—engineered to resist the extreme abrasion of granite and the impact of steel rebar (up to 12mm thick). The cutting edge angle is 135°, with a chamfered tip (a slight bevel on the edge) that reduces “walking” when starting holes in smooth granite surfaces. The DW5490 has an overall length of 180mm (working length: 100mm) and a 3/8-inch shank, compatible with DeWalt’s DCD996 hammer drill (a popular job site tool). It uses 16/24 mesh diamond grit (ultra-coarse) for maximum penetration power, and its matrix is infused with titanium to enhance heat resistance—critical for long drilling sessions (e.g., drilling 20+ holes in a row). A standout feature is its anti-clog flute design, which prevents concrete dust from blocking the flutes (a common issue that slows drilling). In commercial use, the DW5490 can drill 60–80 holes in C40 reinforced concrete or 40–50 holes in granite before needing replacement. It is priced at $40–$50 per unit, used by contractors for projects like installing anchor bolts in concrete walls or cutting holes for HVAC ducts.

A specialized model for precision drilling in brittle materials: glass, porcelain, and quartz countertops. Its matrix hardness is HRC 32 (low), a soft matrix that reduces pressure on brittle materials, preventing cracks. The cutting edge angle is 118°, with a rounded tip (instead of a sharp point) that distributes pressure evenly when starting holes—essential for quartz, which is prone to chipping if the tip is too sharp. The DW5420 has an overall length of 90mm (working length: 40mm) and a 2mm shank, compatible with small precision drills (e.g., DeWalt’s DWE1622K rotary tool). It uses 50/60 mesh diamond grit (fine), which creates smooth, burr-free holes—critical for installing small fixtures like quartz countertop soap dispensers. The bit also features a water-fed core (a small channel in the shank) that delivers water directly to the tip, ensuring constant cooling (glass drilling requires wet conditions to prevent overheating and cracking). In practice, the DW5420 can drill 100–120 holes in 5mm-thick glass or 80–100 holes in porcelain before grit dulling. It is priced at $12–$18 per unit, used by cabinet makers and countertop installers for precision work.

Makita is known for its compact, lightweight tools, and its diamond drill bits follow this philosophy—they are designed to be easy to handle (reducing user fatigue) while maintaining professional performance. The brand’s models often have slightly lower HRC ratings than DeWalt but use high-quality diamond grit to compensate.

A versatile model for home and light professional use, suitable for ceramic tile, marble, and soft concrete (C20 grade). Its matrix hardness is HRC 38 (medium-low), a soft enough matrix to handle tile without chipping but durable enough for concrete. The cutting edge angle is 120°, a balanced angle that works well for both tile (sharp enough to score) and concrete (durable enough to resist aggregate). The D-63727 has an overall length of 120mm (working length: 60mm) and a 3mm shank, compatible with Makita’s HP1641K impact drill (a lightweight model popular among DIYers). It uses 40/50 mesh diamond grit (medium-fine) and a copper-based matrix (softer than cobalt but more corrosion-resistant), making it ideal for indoor projects (e.g., bathroom tile installation) where moisture is present. A key feature is its ergonomic shank design—a slightly tapered shape that fits comfortably in drill chucks, reducing slippage. In use, the D-63727 can drill 60–80 holes in ceramic tile or 20–30 holes in C20 concrete. It is priced at $10–$15 per unit, a top seller in home improvement stores like Home Depot.

Built for professional concrete work (C30 grade) and sandstone, this model balances durability and lightweight design. Its matrix hardness is HRC 45 (medium-high), a cobalt-copper alloy matrix that offers better wear resistance than pure copper but is lighter than DeWalt’s tungsten-cobalt matrices. The cutting edge angle is 132°, a wide angle that provides stability in concrete while maintaining drilling speed. The D-63733 has an overall length of 190mm (working length: 110mm) and a 1/2-inch shank, compatible with Makita’s HR2641X5 hammer drill (a popular choice for residential contractors). It uses 30/40 mesh diamond grit (coarse) and a vacuum-brazed manufacturing process—this bonds the diamond grit more tightly to the matrix, reducing diamond loss during drilling. The bit also features wide flutes that quickly remove concrete dust, preventing clogging and overheating. In professional use, the D-63733 can drill 50–70 holes in C30 concrete or 120–140 holes in sandstone. It is priced at $25–$35 per unit, favored by contractors who need a lightweight bit for all-day use (e.g., drilling holes for drywall anchors in concrete ceilings).

Makita’s industrial-grade large-diameter model, designed for drilling holes in thick masonry (e.g., concrete walls, brick chimneys) and granite countertops. Its matrix hardness is HRC 50 (high), a cobalt-tungsten matrix that resists wear from thick concrete (up to 300mm thick) and granite. The cutting edge angle is 135°, with a double-cutting edge (two sets of diamond grit on the tip) that increases drilling speed by 30% compared to single-edge bits. The D-63740 has an overall length of 250mm (working length: 150mm) and a 3/4-inch shank, compatible with large 台钻 and masonry drills. It uses 20/30 mesh diamond grit (extra-coarse) and a heat-resistant coating that prevents the matrix from softening during high-speed drilling (up to 2,500 RPM). A unique feature is its centering tip—a small, sharp metal point at the center of the diamond tip that helps align the bit on the drilling mark, reducing “walking” in thick masonry. In industrial settings, the D-63740 can drill 30–40 holes in 300mm-thick C30 concrete or 20–30 holes in granite countertops. It is priced at $50–$65 per unit, used by commercial masons and stone fabricators.

Hilti is a luxury brand in construction tools, known for its high-performance, long-lasting products. Its diamond drill bits are engineered for extreme conditions (e.g., industrial manufacturing, heavy civil engineering) and feature the highest HRC ratings and most advanced diamond technology.

A premium home/professional model for brittle materials: glass, porcelain, and natural stone (e.g., marble, onyx). Its matrix hardness is HRC 36 (medium-low), a proprietary “SoftGrip” matrix that adapts to brittle materials—hard enough to retain diamonds but soft enough to avoid cracking. The cutting edge angle is 118°, with a polished tip that reduces friction on glass, creating ultra-smooth holes (no post-processing needed). The TE-CX has an overall length of 100mm (working length: 50mm) and a 3mm shank with Hilti’s SDS-plus design—a quick-change system that allows users to swap bits in seconds (critical for DIYers who switch between materials). It uses 55/65 mesh diamond grit (extra-fine), sourced from premium diamond mines in Botswana (known for high-purity diamonds), ensuring consistent sharpness. The bit also features a water-retention groove (a small channel around the tip) that holds water during drilling, eliminating the need for constant water pouring. In use, the TE-CX can drill 120–150 holes in 5mm glass or 90–110 holes in porcelain, twice the lifespan of Bosch’s HC850. It is priced at $20–$28 per unit, popular among luxury home renovators (e.g., installing glass shower enclosures).

Designed for heavy-duty concrete work (C40–C50 grade) and basalt (one of the hardest natural stones), this model is a staple on industrial job sites. Its matrix hardness is HRC 58 (very high), the highest among the brands discussed—made of a tungsten-cobalt-nickel alloy that resists wear from C50 concrete (used in high-rise buildings) and basalt (莫氏硬度 8). The cutting edge angle is 138°, a extra-wide angle that can withstand impacts from 16mm-thick steel rebar without tip damage. The TE-CX 12mm has an overall length of 180mm (working length: 100mm) and a SDS-plus shank, compatible with Hilti’s TE 70-A36 hammer drill (a industrial-grade tool with 1,200 watts of power). It uses 12/20 mesh diamond grit (ultra-coarse) and a nanocoating—a thin layer of titanium nitride that reduces friction and heat buildup by 40%. The bit also features reinforced flutes (thicker metal around the flutes) that prevent bending in thick concrete. In industrial testing, the TE-CX 12mm can drill 100–120 holes in C50 concrete or 50–60 holes in basalt, outperforming DeWalt’s DW5490 by 25%. It is priced at $60–$75 per unit, used by civil engineers for projects like building bridges or tunnels.

Hilti’s flagship industrial model, built for drilling large holes in extreme materials: reinforced concrete columns (C60 grade), granite boulders, and industrial ceramic (used in factories). Its matrix hardness is HRC 60 (maximum for consumer-accessible bits), a military-grade alloy that can withstand temperatures up to 600°C (common in long drilling sessions). The cutting edge angle is 140°, the widest angle in Hilti’s lineup, with a triple-cutting edge (three sets of diamond grit) that maximizes penetration power. The TE-CX 25mm has an overall length of 300mm (working length: 180mm) and a SDS-max shank, compatible with Hilti’s TE 1000-A36 heavy-duty drill (used in mining and construction). It uses 8/16 mesh diamond grit (industrial-grade coarse) and a pressure-bonded diamond layer—this embeds diamonds deeper into the matrix, ensuring they do not fall out even when drilling through steel rebar. A standout feature is its integrated cooling system—a small channel in the shank that connects to a water pump, delivering a constant flow of water to the tip (critical for drilling 300mm-thick concrete). In industrial use, the TE-CX 25mm can drill 40–50 holes in C60 concrete or 25–35 holes in granite boulders. It is priced at $120–$150 per unit, used by mining companies, nuclear power plants, and large construction firms.

Dongcheng is a leading Chinese power tool brand, offering affordable diamond drill bits that mimic the performance of international brands at a lower price. Its models are ideal for budget-conscious DIYers and small construction companies.

A budget-friendly home model for ceramic tile, glass, and soft marble. Its matrix hardness is HRC 33 (low), a copper-based matrix that is soft enough to avoid tile chipping but durable enough for occasional use. The cutting edge angle is 118°, a standard sharp angle for brittle materials. The Z1J-FF02-6 has an overall length of 100mm (working length: 50mm) and a 3mm shank, compatible with most cheap 手电钻. It uses 45/55 mesh diamond grit (medium-fine), sourced from Chinese diamond mines (lower purity than Hilti’s but sufficient for home use). The bit features a simple spiral flute design that channels water and debris, though it is less effective than Bosch’s flutes at preventing clogging. In use, the Z1J-FF02-6 can drill 30–50 holes in ceramic tile or 20–30 holes in glass, making it suitable for one-time home projects (e.g., installing a tile backsplash). It is priced at $3–$5 per unit, sold in packs of 5 or 10 on e-commerce platforms like Amazon and Alibaba.

A mid-range model for small construction companies, designed for soft concrete (C25 grade) and limestone. Its matrix hardness is HRC 40 (medium), a cobalt-copper alloy that offers better wear resistance than the Z1J-FF02-6. The cutting edge angle is 125°, a balanced angle for concrete and limestone. The Z1J-FF03-10 has an overall length of 150mm (working length: 80mm) and a 1/4-inch hex shank, compatible with Dongcheng’s J1Z-FF05-10 impact drill. It uses 35/45 mesh diamond grit (medium-coarse) and a hot-pressed manufacturing process—this bonds the grit to the matrix more tightly than budget models, reducing diamond loss. The bit also features wide flutes that improve debris removal, though they are thinner than DeWalt’s (prone to bending if hitting rebar). In practice, the Z1J-FF03-10 can drill 20–30 holes in C25 concrete or 80–100 holes in limestone. It is priced at $8–$12 per unit, popular among small renovation companies in developing countries.

Dongcheng’s top-tier professional model, targeting medium-hard concrete (C30 grade) and granite. Its matrix hardness is HRC 48 (medium-high), a cobalt-tungsten alloy that mimics the performance of Bosch’s HC900 but at a lower price. The cutting edge angle is 135°, a wide angle for concrete and granite. The Z1J-FF04-16 has an overall length of 200mm (working length: 120mm) and a 5/8-inch shank, compatible with large hammer drills. It uses 25/35 mesh diamond grit (coarse) and a plated diamond layer—this adds a thin layer of extra diamonds on top, extending the bit’s lifespan. The bit features reinforced flutes and a chamfered tip (to prevent walking), though the matrix is less durable than Hilti’s (prone to wear after 40–50 concrete holes). In use, the Z1J-FF04-16 can drill 30–40 holes in C30 concrete or 20–30 holes in granite. It is priced at $20–$28 per unit, a cost-effective choice for small commercial contractors (e.g., installing retail store fixtures in concrete floors).

In summary, the “degree” of a diamond drill bit is not a single metric but a combination of matrix hardness (HRC/HRB rating) and cutting edge angle (118°–140°), each tailored to specific materials and use cases. Low-HRC (30–35) and narrow-angle (118°) bits are for brittle materials like glass and tile; medium-HRC (40–48) and middle-angle (120°–130°) bits are for soft concrete and marble; high-HRC (50–60) and wide-angle (135°–140°) bits are for reinforced concrete and granite. Leading brands translate these degree specifications into practical models: Bosch balances affordability and versatility, DeWalt focuses on professional durability, Makita prioritizes lightweight efficiency, Hilti offers premium industrial performance, and Dongcheng provides budget-friendly options. Understanding these degrees and brand models is essential for choosing the right drill bit—whether for a DIY tile project, a residential renovation, or an industrial construction job—ensuring optimal drilling speed, hole quality, and tool lifespan.

If you need more details on a specific brand, material application, or technical parameter (e.g., how to measure matrix hardness, or which degree is best for drilling into quartzite), feel free to share additional requirements. I can also provide comparisons between specific models (e.g., Bosch HC900 vs. Hilti TE-CX 12mm) or explain advanced topics like diamond grit mesh sizes and their impact on performance.