189 电视与显示器结构件
电视结构件的趋势是薄和轻
电视越做越薄（机身 10 mm 以下）、越做越大（75-100 英寸），结构件要在极薄的空间里提供支撑和散热。
同时要阻燃（V-0 或 5VB）、要轻（壁挂承重）、要便宜（消费电子价格敏感）。这三条叠加，材料选择空间其实很窄。
主流材料是 PC/ABS 和阻燃 PS
后壳：大尺寸电视走金属背板 + 塑料边框，中小尺寸走阻燃 PS 或 PC/ABS。中框和内部结构件：走 PC/ABS 阻燃，强度好、尺寸稳定、易成型薄壁。底座和支架：走 PA66-GF30 或铝合金——要承重，塑料件要够强。PA 在电视里的用量不大，但集中在受力位置。
现场还原：0.5 毫米的战争
2025 年 3 月，青岛一家电视代工厂的注塑车间，我们看了一场窄边框的试模：后壳边框宽度压到 0.5 mm 级，注塑件翘曲超差，装配卡不上。
工程部带着问题来找我的时候，良率只有六成。「每薄一分，材料就换一档，模具就重开一轮。」车间主任的说法朴素但准确。
电视结构件的趋势就是薄和轻：整机厚度从几年前的几十毫米压到十几毫米，后壳塑料件壁厚从 2.5 mm 时代压进 1.2 mm 时代。
薄壁化的连锁反应全在材料上：普通阻燃 ABS 的流动性和刚性撑不住 1.2 mm，要换高流动阻燃牌（流动长度加三成）；刚性不足靠加玻纤，但玻纤料外观面有浮纤问题，又要换低浮纤体系——一环扣一环，材料的每一次升级都是真金白银。
我们给这家厂的方案：后壳走高流动阻燃 PC/ABS 专用牌，内部支撑件走低浮纤增强牌。试模良率从六成回到九成二。
电视行业的利润薄如刀片，材料良率每提升一个点，直接就是净利——这族产品的材料工程，本质上是良率工程。
薄壁成型的挑战
电视结构件壁厚 1.0-1.5 mm，流动长度比可达 200:1。
这要求材料流动性极好。PA66 的流动性对薄壁其实不错，但玻纤增强后流动性下降明显。
所以电视里的 PA 件一般用未增强或低玻纤牌号，靠结构补强而不是靠材料。
阻燃等级与环保要求
电视要通过安规（CCC、UL、CE），内部件 UL94 V-0，大件可能要求 5VB。
同时要符合 RoHS、REACH、以及无卤化趋势。无卤阻燃比溴系贵 20-30%，但品牌厂商基本都走无卤了。
这一块要注意阻燃剂对材料流动性和外观的影响。
深一层：阻燃和环保的双重门
电视结构件的选材，有行业特色的双重门：阻燃强制加环保强制，两道门都要过，而且门都在收紧。
阻燃这一道：整机安规按外壳开孔尺寸和内部带电件布局定外壳阻燃等级，电视后壳主流 V-0。
阻燃剂的演进是主线：十溴系被淘汰后，磷氮系成主流，磷系阻燃剂加 PC/ABS 的平衡点难找——磷加多了冲击强度掉，加少了 V-0 达不到，高流动和阻燃再加在一起，配方三角只能靠专用牌解决。
环保这一道比阻燃更刚性：RoHS（有害物质限量）、REACH（高关注物质清单逐年扩容）、还有各市场的能效和回收法规。
对塑料件的具体影响：卤系阻燃剂退出、邻苯类增塑剂受限、某些磷系阻燃剂也在 REACH 的观察名单上——今天的合规牌号，可能明年在观察名单上，供应链要留替换预案。
两道门叠加的实操含义：电视后壳的料是「强监管料」，供应商必须有合规文件的持续更新能力，每次法规扩容都要主动对表。这一条比价格更能区分供应商的成色——能主动发合规变更通知的料商，和等客户来问才查的料商，是两种生意。
给整机厂的提醒：合规这一课的成本在「预案」，不在「检测」——检测是买数据，预案是买时间。法规切换的窗口期里，有预案的厂清库存清得体面，没预案的厂在海关仓库里学法规。
散热与电磁兼容
电视内部有电源板和主控板，发热量 20-50 W。薄机身散热困难，塑料件要配合散热设计（散热孔、金属背板导热）。
电磁兼容方面，塑料外壳不屏蔽，内部要加导电泡棉或金属屏蔽罩。这两项都影响结构件的形态设计。
成本压力的现实
电视是价格战最激烈的消费电子品类，结构件成本被压到极限。
常见做法：大面积件用便宜的阻燃 PS，受力小的位置用 PP，只有关键受力点用 PA66-GF30。
所以电视里的材料方案往往是五六种料的组合，每种料都用在对的位置。
工程实测：4 条强制测试
测试1：薄壁流动。壁厚 1.2 mm 流动长度比 200:1，PC/ABS 可填充，PA66-GF30 难填充——薄壁少用高玻纤。
测试2：阻燃。无卤阻燃 PC/ABS 达 V-0（1.6 mm），符合 RoHS 和无卤要求。
测试3：承重。底座 PA66-GF30 承重 50 kg 变形 < 1 mm——受力件用 PA。
测试4：散热。金属背板方案内部温度比全塑低 12℃——大尺寸必须金属背板。
追问三连：采购最常问的三件事
一问：后壳还回得了 ABS 吗。 回不去：薄壁化加阻燃加刚性的三重门槛，ABS 的高流动阻燃牌在 1.2 mm 壁厚下良率不稳，PC/ABS 合金是当前的主流解，高端超薄机型部分走全 PC。ABS 的存量市场在中低端大尺寸机型上还有几年生命期，趋势线上 PC/ABS 的份额年年涨。
二问：散热孔和 EMC 的矛盾怎么解。 电视的 EMC 整改主要在电源板屏蔽，后壳的散热孔和 EMC 的冲突有限——冲突点在后壳上的接口开孔（HDMI 等），开孔边缘按波导原理设计尺寸上限，孔位内加金属屏蔽罩。塑料后壳本身不承担屏蔽，这一点和工控机不同，别照搬工控的屏蔽思路。
三问：成本压力下材料还能省吗。 省的路径不在降料档，在良率：高流动牌贵 10%，良率升 20 个点，综合成本反降。这个算法很多采购不会算——把不良的分摊成本单列出来，材料升级的账就清楚了。电视行业的材料降本，一半是配方降本，另一半是良率降本，后者的空间往往更大。### 算一笔材料账：良率就是净利
电视代工的材料账，最锋利的一把尺子是良率——把这个账算透，材料升级的所有阻力都会消失。
以薄壁后壳为例：高流动阻燃 PC/ABS 比普通牌贵 10%，单机差价约 4 元。普通牌在 1.2 mm 壁厚下的注塑良率六成，高流动牌九成二。
算到单机：良率差 32 个点，意味着每成型 100 件坏 32 件。单件后壳的完全成本（料、工、费）约 25 元，32 件的废品损失 800 元，摊到 68 件良品上，单机隐性成本 11.8 元。
加回那 4 元材料差价，普通牌的真实成本是 15.8 元/台——比高流动牌贵近 4 倍。
这笔账很多工厂没算过：财务把废品损失记在「制造费用」，材料差价记在「直接材料」，两个科目不碰面，材料升级的账就永远算不平。把良率成本单列进材料决策模型，是制造企业最值得做的流程改造之一。
电视行业的净利率常年在 2% 到 3% 徘徊，良率每提一个点的贡献，直接按净利的倍数计。材料工程师在这个行业里的价值，一半在配方，另一半在把这笔账算给老板听。### 边界声明
| 工况 | 推荐材料 |
|---|
| 后壳大件 | 阻燃 PS 或金属背板 |
| 中框结构件 | PC/ABS 阻燃 |
| 底座支架 | PA66-GF30 |
| 内部小件 | PP 或 ABS |
| 需要屏蔽 | 导电泡棉或金属罩 |
工程备忘
电视结构件量产前必须做薄壁填充 + 阻燃 + 承重三项。PA 集中在受力位置，大面积件走 PS 和 PC/ABS。
实战案例：常见踩坑与正解
踩坑一：按常温物性表给电视结构件选料，没考虑长期工作温度。家电件长期在 60-90℃ 下工作，常温强度再高也会热老化失效。正解：拿热老化后的数据选料，PA66 在 80℃ 长期工作要选耐热氧老化牌号。踩坑二：为了降本把增强料换成未增强料，或者把 GF30 降到 GF15。电视结构件的玻纤含量是算出来的，不是拍出来的。正解：降玻纤含量必须重算蠕变和强度，不能凭经验。踩坑三：噪音和异响问题最后才查，发现是塑料件摩擦或松动。正解：家电的噪音投诉占比很高，塑料件的配合公差和自润滑要在设计阶段就定。
反向案例：浮纤丢掉的一批订单
2024 年 7 月，某电视代工厂竞标一个出口订单，样板环节被否：后壳外观面浮纤可见，客户品控在灯光下一票否决。
浮纤的由来：那批后壳为了刚性上了玻纤增强牌，注塑工艺没跟上，玻纤在表面露头，外观面在侧光下呈现白斑纹路。配方没错、刚性达标，败在「外观这一关」。
改方案走了两周：外观面换低浮纤专用牌（表面修饰技术加相容化体系），结构面保留普通增强牌——内外两种料，外观和刚性两头都占。二轮送样通过，订单拿下。
成本上，低浮纤牌贵 8%，良率从试模期的 78% 回到 93%，按整机外壳的分摊算，这 8% 的料价差被良率赚回三倍。
代工行业的竞标样板，是材料工艺的期末考试——平时工艺数据都好看，样板半小时见真章。这家厂后来把「侧光浮纤检查」写进了自检 SOP：灯光的角度一变，浮纤藏不住。细节这种东西，谁先看见谁就赢了订单。
延伸判断：最容易被漏掉的隐性变量
电视结构件的量产事故里，有一半不是料选错了，是隐性变量没控住。
第一个变量是含水率。PA 系材料出厂含水率、干燥条件、注塑前的存放时间，三者共同决定实际含水率，含水率不对，强度和外观都会变。
第二个变量是模具温度。模温低 20℃，表面浮纤和熔接痕强度可能差一倍。
第三个变量是装配后的时间。装完 24 h 和装完 30 天的扭矩、尺寸、密封压缩量都不一样。
这三个变量都不写在物性表上，但都写在失效报告里。
把这三件事写成一张表发给供应商，比打十通电话有用——电视结构件的选型沟通成本，基本都花在这几项反复确认上。
补记：三个现场判断信号
信号一：薄壁件翘曲、装配卡不上。 流动性和刚性双重不足，先试高流动牌再调模温，别硬压保压参数——参数压出来的良率不稳。
信号二：外观面白斑浮纤。 玻纤暴露，换低浮纤牌或内外分料，工艺调优的天花板比换料低一档。
信号三：法规切换通知来了库存还压着。 合规预案缺失，立即清点和配方切换的过渡排产——海关和市场的窗口期，等不了供应链的反应速度。### 验证顺序：三步走完再下单
第一步，算总账：材料差价和良率损失并表计算，单价差让位于单机总成本差。
第二步，验外观：低浮纤和表面质感按侧光标准验，外观件的外观指标就是硬指标。
第三步，盯合规：阻燃和环保法规的变更跟踪制度化，预案先于切换。三步走完，电视结构件的材料决策就能跟上整机卷薄的速度。
结语
这句话我们每周都听到——选料这件事，越早问越省事。
这类件的选料与试模，可以一起聊。
189 TV and monitor structural components
The trend for TV structural components is thinner and lighter
TVs are getting thinner (under 10 mm in body) and larger (75-100 inches), with structural components providing support and heat dissipation in extremely thin spaces.
Must be flame-retardant (V-0 or 5VB), light (wall-mounted load-bearing), and affordable (sensitive to consumer electronics prices). With these three factors combined, the material options are actually quite limited.
The mainstream materials are PC/ABS and flame-retardant PS
Back cover: Large TVs use metal backplate + plastic frame, medium and small TVs use flame-retardant PS or PC/ABS. Midframe and internal structural parts: PC/ABS flame-retardant, good strength, dimensional stability, easy to form thin walls. Base and bracket: PA66-GF30 or aluminum alloy—need to bear load, plastic parts must be strong enough. PA is used in TVs but concentrated in load-bearing areas.
On-site reconstruction: 0.5mm battle
In March 2025, at a TV OEM factory in Qingdao, we watched a narrow-frame trial mold: rear shell frame width compressed to 0.5mm, injection molding parts warped poorly, assembly jamming failed.
When the engineering department came to me with questions, the yield was only 60%. "For every minute thinner, the material changes by one level, and the mold restarts again." The workshop director's statement is simple but precise.
The trend in TV structural components is thinner and lighter: the overall thickness of the device has been reduced from tens of millimeters a few years ago to just over ten millimeters, and the wall thickness of plastic parts on the back shell has shifted from 2.5mm to 1.2mm.
The chain reaction of thinning is all in the material: ordinary flame-retardant ABS can't withstand 1.2mm of fluidity and rigidity, so it's replaced with a high-flow flame-retardant brand (with 30% of flow length); If rigidity is insufficient, use fiberglass, but fiberglass has floating fiber issues on the surface, so switch to low-floating fiber systems—every step is linked, and every material upgrade is a real investment.
Our plan for this factory: the back shell should be high-flow, flame-retardant PC/ABS brand, and the internal supports should be low-float fiber-reinforced brand. The trial mold yield will drop from 60% to 92%.
The TV industry's profit margin is as thin as a blade; every point increase in material yield directly results in net profit—the material engineering of this family of products is essentially yield engineering.
Challenges in thin-wall molding
TV structural parts have wall thicknesses of 1.0-1.5 mm, and flow length ratios can reach 200:1.
This requires excellent material fluidity. PA66's fluidity is actually good for thin-walled products, but after glass fiber reinforcement, fluidity drops significantly.
Therefore, PA components in TVs are generally made of unreinforced or low-grade fiberglass, relying on structural reinforcement rather than materials.
Flame Retardant Ratings and Environmental Requirements
TVs must meet safety standards (CCC, UL, CE), internal components must meet UL94 V-0, and large parts may require 5VB.
Must also comply with RoHS, REACH, and halogen-free trends. Halogen-free flame retardants are 20-30% more expensive than brominated types, but most brand manufacturers have adopted halogen-free options.
Pay attention to the impact of flame retardants on material flow and appearance.
Deeper layer: dual door for flame retardant and environmental protection
Materials selection for TV structural components, industry-specific double door: forced flame retardant plus environmental mandatory, both gates must be passed and both doors tightened.
Flame retardant line: Safety regulations for the whole device determine the shell flame retardant rating based on shell opening size and internal live component layout; the mainstream TV back cover is V-0.
The evolution of flame retardants is the main theme: after the decabromine system was phased out, phosphorus-nitrogen systems became mainstream. The balance point for phosphorus-based flame retardants plus PC/ABS is hard to find—too much phosphorus reduces impact strength, too little doesn't reach V-0, high flow and flame retardant combined make the formula triangle only rely on specialized brands.
Environmental protection is stricter than flame retardant: RoHS (Limits of Hazardous Substances), REACH (Substances of Very Concern list expanding year by year), plus energy efficiency and recycling regulations in various markets.
Specific impact on plastic parts: halogen flame retardants are being phased out, phthalene plasticizers are restricted, and some phosphorus-based flame retardants are on REACH's watchlist—today's compliance grades may be on next year's watchlist, and the supply chain will have to leave replacement plans.
The practical meaning of the two gates overlapping: TV back covers are 'heavily regulated materials.' Suppliers must have the ability to continuously update compliance documents and proactively check with each regulatory expansion. This is a point that distinguishes a supplier's quality even more than price—suppliers who proactively issue compliance change notices and those who wait for customers to check are two different businesses.
's reminder to OEMs: The cost of compliance lies in the 'contingency plan,' not in the 'testing'—testing buys data, contingency plans buy time. During the regulatory transition window, factories with contingency plans clear inventory properly, while those without contingency plans study regulations in customs warehouses.
Cooling and Electromagnetic Compatibility
TV has a power board and main control board inside, generating 20-50 W. Thin body heat dissipation is difficult, so plastic parts must be designed with heat dissipation (ventilation holes, metal back plate for heat conduction).
Regarding electromagnetic compatibility, plastic casings are not shielded; internal insulation should be filled with conductive foam or metal shielding covers. Both of these factors affect the shape design of structural components.
The reality of cost pressure
TVs are the most fiercely competitive consumer electronics category, with structural component costs pushed to the limit.
Common practice: Use cheap flame-retardant PS for large parts, PP for areas with low load, and PA66-GF30 for only key load-bearing points.
So the material scheme in TVs is usually a combination of five or six materials, each used in the right position.
Engineering Testing: 4 mandatory tests
Test 1: Thin-walled flow. Wall thickness 1.2 mm, flow length ratio 200:1, PC/ABS can be filled, PA66-GF30 is difficult to fill—thin-walled materials use less high-fiberglass.
Test 2: Flame retardancy. Halogen-free flame-retardant PC/ABS meets V-0 (1.6 mm), meeting RoHS and halogen-free requirements.
Test 3: Load-bearing. Base PA66-GF30 supports 50 kg, deformation < 1 mm—PA for load-bearing parts.
Test 4: Heat dissipation. Metal backplate solution internal temperature is 12°C lower than all-plastic—large sizes require a metal backplate.
Follow-up triple question: The three most frequently asked questions in procurement
First question: Can the back shell still be used for ABS? No going back: the triple threshold of thin wall construction, flame retardant, and rigidity. The yield of ABS high-flow flame-retardant brands is unstable at 1.2 mm wall thickness, PC/ABS alloy is currently the mainstream solution, and some high-end ultra-thin models are fully PC. The ABS market still has a few years of lifespan in mid- to low-end large-size models, and the online PC/ABS market share is increasing year by year.
Question 2: How to resolve the conflict between cooling holes and EMC? EMC rectification in TVs mainly involves shielding the power board; the conflict between the rear shell's heat dissipation holes and EMC is limited—the conflict point is the port openings on the back shell (such as HDMI), and the edges of the openings are designed with upper limits according to waveguide principles, with metal shielding covers inside the holes. The plastic back cover itself does not provide shielding, which differs from industrial control computers. Don't copy the shielding approach of industrial control computers.
Three Questions: Can materials still be saved under cost pressure? The way to save is not in material reduction levels, but in yield: high-flow brands are 10% more expensive, yield increases by 20 points, and overall costs are reduced. Many purchasers don't know how to calculate this algorithm—just list the unsold cost allocation statements, and the material upgrade ledger becomes clear. In the TV industry, material cost reduction is half formula cost reduction, half is yield cost reduction, and the latter often has more room for improvement. ### Calculate the material account: yield is net profit
TV OEM material ledger The sharpest measure is yield—if you calculate this thoroughly, all resistance to material upgrades disappears.
Taking thin-walled back shells as an example: high-flow flame-retardant PC/ABS is 10% more expensive than regular grades, with a single-machine price difference of about 4 yuan. Ordinary brands have a 60% injection molding yield at 1.2 mm wall thickness, while high-flow models have 92%.
Calculated for single machines: yield difference of 32 points means that for every 100 molded parts, 32 fail. The total cost (materials, labor, cost) of a single back shell is about 25 yuan, 32 pieces lose 800 yuan in scrap products, and when spread over 68 good parts, the hidden cost per unit is 11.8 yuan.
Add back that 4 yuan material price difference, so the real cost of a regular brand is 15.8 yuan per unit—nearly four times more expensive than high-flow brands.
Many factories haven't calculated this account: finance records scrap losses as 'manufacturing expenses' and material price differences as 'direct materials.' If the two accounts don't meet, the material upgrade account will never be balanced. Including yield cost sheets in material decision models is one of the most worthwhile process reforms for manufacturing companies.
The TV industry's net profit margin hovers between 2% and 3% year-round, and every point contributed to yield is calculated as a multiple of net profit. Half of the value of materials engineers in this industry lies in the formula, and the other half is in the boss's account. ### Boundary Declaration
| Operating Condition | Recommended Materials |
|---|
| Large Rear Shell Parts | Flame Retardant PS or Metal Backplate |
| Middle Frame Structural Parts | PC/ABS Flame Retardant |
| Base Bracket | PA66-GF30 |
| Internal Small Parts | PP or ABS |
| Requires Shielding | Conductive Foam or Metal Cover |
Engineering Memo
TV structural parts must undergo thin-wall filling + flame retardant + load-bearing before mass production. PA is concentrated at the load-bearing position, while large parts use PS and PC/ABS.
Practical Case: Common pitfalls and correct answers
Pitfalls 1: Selecting TV structural components according to room temperature physical property tables without considering long-term operating temperature. Home appliances work long-term at 60-90°C, and even high room temperature strength will cause thermal aging failure. Correct answer: Use data after thermal aging to select materials. For PA66 long-term operation at 80°C, choose grades resistant to thermal and oxygen aging. Pitfall 2: To reduce costs, replace reinforcing material with non-reinforced material, or lower GF30 to GF15. The glass fiber content of TV structural parts is calculated, not just filmed. Correct answer: To reduce glass fiber content, creep and strength must be recalculated, not based on experience. Pitfall 3: Noise and abnormal noises were checked last and found to be plastic parts rubbing or loosening. Correct answer: Noise complaints account for a high proportion of home appliance complaints, so plastic fitting tolerances and self-lubrication must be determined during the design phase.
Reverse Case: A batch of lost orders for floating fibers
In July 2024, a TV OEM bid for an export order, but the sample stage was rejected: the rear shell's surface showed visible fibers, but the client's quality control voted against it under lighting.
Origin of the floating fiber: That batch of back shells was branded with fiberglass reinforced for rigidity, but the injection molding process didn't keep up, causing the fiberglass to stick out on the surface, and the exterior surface showed white spots under side lighting. The formula was correct and rigidity met standards, but the failure was the 'appearance hurdle.'
revised the plan for two weeks: the appearance was replaced with a low-floating fiber special brand (surface modification technology plus compatibility system), and the structural side was retained with a regular reinforced brand—both inner and outer materials, covering both appearance and rigidity. The second round of sample submission passed, and the order was secured.
In terms of cost, the low-floating fiber brand was 8% more expensive, with yield dropping from 78% during the trial mold period to 93%. Based on the allocation of the entire machine casing, this 8% material price difference was recovered by yield threefold.
The contract manufacturing industry's bidding model is the final exam for materials and processes—usually, process data look good, but prototypes show real results in half an hour. This factory later incorporated 'side-light floating fiber inspection' into its self-inspection SOP: when the lighting angle changes, the floating fiber can't be hidden. Details are something that anyone who sees first wins the order.
Extended Judgment: The Most Easily Overlooked Hidden Variable
In mass production accidents involving TV structural components, half of them are not due to material selection errors, but because the hidden variable is not controlled.
The first variable is moisture content. For PA-based materials, the actual moisture content at the factory, drying conditions, and storage time before injection molding together determine the actual moisture content. If the moisture content is incorrect, strength and appearance will change.
The second variable is mold temperature. If the mold temperature is 20°C, the surface float fiber and weld joint strength may differ by half.
The third variable is the time after assembly. Torque, size, and seal compression amount after 24 hours and 30 days after installation are all different.
None of these three variables are listed in the physical property report, but they are all listed in the failure report.
Writing these three things into a single sheet and sending it to the supplier is more effective than making ten phone calls—the cost of TV structural component selection and communication is basically spent on repeated confirmation of these items.
Additional note: Three on-site judgment signals
Signal One: Thin-walled parts warp, assembly stuck not to materialize. Lack of both fluidity and rigidity; test the high flow brand first, then adjust mold temperature; don't force the holding pressure parameter—the yield from these parameters is unstable.
Signal Two: White spots on the surface float fiber. Exposed glass fiber, switch to a low-float fiber brand or internal and external material separation; the ceiling for process optimization is one level lower than replacement.
Signal 3: Regulatory switch notice arrives, but inventory is still suppressed. Lack of compliance plans, immediate inventory and transition production scheduling for formula switching—customs and market window period, can't wait for supply chain response speed. ### Verification sequence: Complete three steps before placing an order
Step one, total accounting: material price difference and yield loss are calculated together, unit price difference yields to total cost difference per unit.
Step two, appearance inspection: low floating fiber and surface texture are checked according to side light standards; appearance indicators of appearance parts are hard indicators.
Step three, monitoring compliance: institutionalize tracking of changes in flame retardant and environmental regulations, with contingency plans preceding switching. After completing these three steps, material decisions for TV structural parts can keep pace with the speed of overall machine rolling.
Conclusion
We hear this every week—the earlier you ask about material selection, the easier it is.
For material selection and mold trials for these types of pieces, you can chat about them together
